/// <summary>
/// Load stylesheet data from the given source.<br/>
/// The source can be local file or web URI.<br/>
/// First raise <see cref="HtmlStylesheetLoadEventArgs"/> event to allow the client to overwrite the stylesheet loading.<br/>
/// If the stylesheet is downloaded from URI we will try to correct local URIs to absolute.<br/>
/// </summary>
/// <param name="htmlContainer">the container of the html to handle load stylesheet for</param>
/// <param name="src">the source of the element to load the stylesheet by</param>
/// <param name="attributes">the attributes of the link element</param>
/// <param name="stylesheet">return the stylesheet string that has been loaded (null if failed or <paramref name="stylesheetData"/> is given)</param>
/// <param name="stylesheetData">return stylesheet data object that was provided by overwrite (null if failed or <paramref name="stylesheet"/> is given)</param>
public static void LoadStylesheet(HtmlContainerInt htmlContainer, string src, Dictionary<string, string> attributes, out string stylesheet, out CssData stylesheetData)
{
ArgChecker.AssertArgNotNull(htmlContainer, "htmlContainer");
stylesheet = null;
stylesheetData = null;
try
{
var args = new HtmlStylesheetLoadEventArgs(src, attributes);
htmlContainer.RaiseHtmlStylesheetLoadEvent(args);
if (!string.IsNullOrEmpty(args.SetStyleSheet))
{
stylesheet = args.SetStyleSheet;
}
else if (args.SetStyleSheetData != null)
{
stylesheetData = args.SetStyleSheetData;
}
else if (args.SetSrc != null)
{
stylesheet = LoadStylesheet(htmlContainer, args.SetSrc);
}
else
{
stylesheet = LoadStylesheet(htmlContainer, src);
}
}
catch (Exception ex)
{
htmlContainer.ReportError(HtmlRenderErrorType.CssParsing, "Exception in handling stylesheet source", ex);
}
}
/// <summary>
/// Generate css tree by parsing the given html and applying the given css style data on it.
/// </summary>
/// <param name="html">the html to parse</param>
/// <param name="htmlContainer">the html container to use for reference resolve</param>
/// <param name="cssData">the css data to use</param>
/// <returns>the root of the generated tree</returns>
public CssBox GenerateCssTree(string html, HtmlContainerInt htmlContainer, ref CssData cssData)
{
var root = HtmlParser.ParseDocument(html);
if (root != null)
{
root.HtmlContainer = htmlContainer;
bool cssDataChanged = false;
CascadeParseStyles(root, htmlContainer, ref cssData, ref cssDataChanged);
CascadeApplyStyles(root, cssData);
SetTextSelectionStyle(htmlContainer, cssData);
CorrectTextBoxes(root);
CorrectImgBoxes(root);
bool followingBlock = true;
CorrectLineBreaksBlocks(root, ref followingBlock);
CorrectInlineBoxesParent(root);
CorrectBlockInsideInline(root);
CorrectInlineBoxesParent(root);
}
return root;
}
/// <summary>
/// Asigns the given css style blocks to the given css box checking if matching.
/// </summary>
/// <param name="box">the css box to assign css to</param>
/// <param name="cssData">the css data to use to get the matching css blocks</param>
/// <param name="className">the class selector to search for css blocks</param>
private static void AssignCssBlocks(CssBox box, CssData cssData, string className)
{
var blocks = cssData.GetCssBlock(className);
foreach (var block in blocks)
{
if (IsBlockAssignableToBox(box, block))
{
AssignCssBlock(box, block);
}
}
}
/// <summary>
/// Generate css tree by parsing the given html and applying the given css style data on it.
/// </summary>
/// <param name="html">the html to parse</param>
/// <param name="cssData">the css data to use</param>
/// <param name="bridge">used to resolve external style references in html code</param>
/// <returns>the root of the generated tree</returns>
public static CssBox GenerateCssTree(string html, ref CssData cssData, object bridge)
{
var root = HtmlParser.ParseDocument(html);
if (root != null)
{
bool cssDataChanged = false;
CascadeStyles(root, bridge, ref cssData, ref cssDataChanged);
CorrectLineBreaksBlocks(root);
CorrectBlockInsideInline(root);
CorrectInlineBoxesParent(root);
}
return root;
}
public override void SetOn(CssData data)
{
data.AddAttribute(Selector, "font-variant", "small-caps");
}
/// <summary>
/// Parse given stylesheet for media CSS blocks<br/>
/// This blocks are added under the specific media block they are found.
/// </summary>
/// <param name="cssData">the CSS data to fill with parsed CSS objects</param>
/// <param name="stylesheet">the stylesheet to parse</param>
private void ParseMediaStyleBlocks(CssData cssData, string stylesheet)
{
int startIdx = 0;
string atrule;
while ((atrule = RegexParserUtils.GetCssAtRules(stylesheet, ref startIdx)) != null)
{
//Just process @media rules
if (!atrule.StartsWith("@media", StringComparison.OrdinalIgnoreCase))
continue;
//Extract specified media types
MatchCollection types = RegexParserUtils.Match(RegexParserUtils.CssMediaTypes, atrule);
if (types.Count == 1)
{
string line = types[0].Value;
if (line.StartsWith("@media", StringComparison.OrdinalIgnoreCase) && line.EndsWith("{"))
{
//Get specified media types in the at-rule
string[] media = line.Substring(6, line.Length - 7).Split(' ');
//Scan media types
foreach (string t in media)
{
if (!String.IsNullOrEmpty(t.Trim()))
{
//Get blocks inside the at-rule
var insideBlocks = RegexParserUtils.Match(RegexParserUtils.CssBlocks, atrule);
//Scan blocks and feed them to the style sheet
foreach (Match insideBlock in insideBlocks)
{
FeedStyleBlock(cssData, insideBlock.Value, t.Trim());
}
}
}
}
}
}
}
/// <summary>
/// Parse the given stylesheet source to CSS blocks dictionary.<br/>
/// The CSS blocks are organized into two level buckets of media type and class name.<br/>
/// Root media type are found under 'all' bucket.<br/>
/// The parsed css blocks are added to the given css data, merged if class name already exists.
/// </summary>
/// <param name="cssData">the CSS data to fill with parsed CSS objects</param>
/// <param name="stylesheet">raw css stylesheet to parse</param>
public void ParseStyleSheet(CssData cssData, string stylesheet)
{
if (!String.IsNullOrEmpty(stylesheet))
{
stylesheet = RemoveStylesheetComments(stylesheet);
ParseStyleBlocks(cssData, stylesheet);
ParseMediaStyleBlocks(cssData, stylesheet);
}
}
/// <summary>
/// Parse the given stylesheet source to CSS blocks dictionary.<br/>
/// The CSS blocks are organized into two level buckets of media type and class name.<br/>
/// Root media type are found under 'all' bucket.<br/>
/// The parsed css blocks are added to the given css data, merged if class name already exists.
/// </summary>
/// <param name="cssData">the CSS data to fill with parsed CSS objects</param>
/// <param name="stylesheet">raw css stylesheet to parse</param>
public static void ParseStyleSheet(CssData cssData, string stylesheet)
{
if (!String.IsNullOrEmpty(stylesheet))
{
// Convert everything to lower-case so not to handle case in code
stylesheet = stylesheet.ToLower();
stylesheet = RemoveStylesheetComments(stylesheet);
ParseStyleBlocks(cssData, stylesheet);
ParseMediaStyleBlocks(cssData, stylesheet);
}
}
static void Register(//PageFrameCompiler page,
Type cssType)
{
CssData data;
if (!styles.TryGetValue(cssType, out data)) {
data = new CssData();
styles[cssType] = data;
}
}
public override void SetOff(CssData data)
{
}
/// <summary>
/// Assigns the given css classes to the given css box checking if matching.<br/>
/// Support multiple classes in single attribute separated by whitespace.
/// </summary>
/// <param name="box">the css box to assign css to</param>
/// <param name="cssData">the css data to use to get the matching css blocks</param>
private static void AssignClassCssBlocks(CssBox box, CssData cssData)
{
var classes = box.HtmlTag.TryGetAttribute("class");
var startIdx = 0;
while (startIdx < classes.Length)
{
while (startIdx < classes.Length && classes[startIdx] == ' ')
startIdx++;
if (startIdx < classes.Length)
{
var endIdx = classes.IndexOf(' ', startIdx);
if (endIdx < 0)
endIdx = classes.Length;
var cls = "." + classes.Substring(startIdx, endIdx - startIdx);
AssignCssBlocks(box, cssData, cls);
AssignCssBlocks(box, cssData, box.HtmlTag.Name + cls);
startIdx = endIdx + 1;
}
}
}
public override void SetOff(CssData data)
{
data.AddAttribute(Selector, "font-variant", "normal");
}
/// <summary>
/// Create PDF pages from given HTML and appends them to the provided PDF document.<br/>
/// </summary>
/// <param name="document">PDF document to append pages to</param>
/// <param name="html">HTML source to create PDF from</param>
/// <param name="config">the configuration to use for the PDF generation (page size/page orientation/margins/etc.)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
public static void AddPdfPages(PdfDocument document, string html, PdfGenerateConfig config, CssData cssData = null, EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
XSize orgPageSize;
// get the size of each page to layout the HTML in
if (config.PageSize != PageSize.Undefined)
{
orgPageSize = PageSizeConverter.ToSize(config.PageSize);
}
else
{
orgPageSize = config.ManualPageSize;
}
if (config.PageOrientation == PageOrientation.Landscape)
{
// invert pagesize for landscape
orgPageSize = new XSize(orgPageSize.Height, orgPageSize.Width);
}
var pageSize = new XSize(orgPageSize.Width - config.MarginLeft - config.MarginRight, orgPageSize.Height - config.MarginTop - config.MarginBottom);
if (!string.IsNullOrEmpty(html))
{
using (var container = new HtmlContainer())
{
if (stylesheetLoad != null)
{
container.StylesheetLoad += stylesheetLoad;
}
if (imageLoad != null)
{
container.ImageLoad += imageLoad;
}
container.Location = new XPoint(config.MarginLeft, config.MarginTop);
container.MaxSize = new XSize(pageSize.Width, 0);
container.SetHtml(html, cssData);
container.PageSize = pageSize;
container.MarginBottom = config.MarginBottom;
container.MarginLeft = config.MarginLeft;
container.MarginRight = config.MarginRight;
container.MarginTop = config.MarginTop;
// layout the HTML with the page width restriction to know how many pages are required
using (var measure = XGraphics.CreateMeasureContext(pageSize, XGraphicsUnit.Point, XPageDirection.Downwards))
{
container.PerformLayout(measure);
}
// while there is un-rendered HTML, create another PDF page and render with proper offset for the next page
double scrollOffset = 0;
while (scrollOffset > -container.ActualSize.Height)
{
var page = document.AddPage();
page.Height = orgPageSize.Height;
page.Width = orgPageSize.Width;
using (var g = XGraphics.FromPdfPage(page))
{
//g.IntersectClip(new XRect(config.MarginLeft, config.MarginTop, pageSize.Width, pageSize.Height));
g.IntersectClip(new XRect(0, 0, page.Width, page.Height));
container.ScrollOffset = new XPoint(0, scrollOffset);
container.PerformPaint(g);
}
scrollOffset -= pageSize.Height;
}
// add web links and anchors
HandleLinks(document, container, orgPageSize, pageSize);
}
}
}
/// <summary>
/// Init with optional document and stylesheet.
/// </summary>
/// <param name="htmlSource">the html to init with, init empty if not given</param>
/// <param name="baseCssData">optional: the stylesheet to init with, init default if not given</param>
public void SetHtml(string htmlSource, CssData baseCssData = null)
{
_htmlContainerInt.SetHtml(htmlSource, baseCssData);
}
/// <summary>
/// Only used as a commodity during testing.
/// </summary>
public override void InsertCss(CssData cssData)
{
InsertCss(new CssPropertiesSet(), cssData);
}
/// <summary>
/// Create PDF pages from given HTML and appends them to the provided PDF document.<br/>
/// </summary>
/// <param name="document">PDF document to append pages to</param>
/// <param name="html">HTML source to create PDF from</param>
/// <param name="config">the configuration to use for the PDF generation (page size/page orientation/margins/etc.)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
public static void AddPdfPages(PdfDocument document, string html, PdfGenerateConfig config, CssData cssData = null, EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
XSize orgPageSize;
// get the size of each page to layout the HTML in
if (config.PageSize != PageSize.Undefined)
{
orgPageSize = PageSizeConverter.ToSize(config.PageSize);
}
else
{
orgPageSize = config.ManualPageSize;
}
if (config.PageOrientation == PageOrientation.Landscape)
{
// invert pagesize for landscape
orgPageSize = new XSize(orgPageSize.Height, orgPageSize.Width);
}
var pageSize = new XSize(orgPageSize.Width - config.MarginLeft - config.MarginRight, orgPageSize.Height - config.MarginTop - config.MarginBottom);
if (!string.IsNullOrEmpty(html))
{
using (var container = new HtmlContainer())
{
if (stylesheetLoad != null)
{
container.StylesheetLoad += stylesheetLoad;
}
if (imageLoad != null)
{
container.ImageLoad += imageLoad;
}
container.Location = new XPoint(config.MarginLeft, config.MarginTop);
container.MaxSize = new XSize(pageSize.Width, 0);
container.SetHtml(html, cssData);
container.PageSize = pageSize;
container.MarginBottom = config.MarginBottom;
container.MarginLeft = config.MarginLeft;
container.MarginRight = config.MarginRight;
container.MarginTop = config.MarginTop;
// layout the HTML with the page width restriction to know how many pages are required
var measure = XGraphics.CreateMeasureContext(pageSize, XGraphicsUnit.Point, XPageDirection.Downwards);
container.PerformLayout(measure);
// while there is un-rendered HTML, create another PDF page and render with proper offset for the next page
double scrollOffset = 0;
//SL: if there is more than one page, increase the bottom margin to allow space for the page number
container.MarginBottom += scrollOffset > -container.ActualSize.Height ? 20 : 0;
container.PerformLayout(measure); //SL: This still does not increase the margin for the first page of a multi page.. welp
while (scrollOffset > -container.ActualSize.Height)
{
var page = document.AddPage();
page.Height = orgPageSize.Height;
page.Width = orgPageSize.Width;
using (var g = XGraphics.FromPdfPage(page))
{
//g.IntersectClip(new XRect(config.MarginLeft, config.MarginTop, pageSize.Width, pageSize.Height));
g.IntersectClip(new XRect(0, 0, page.Width, page.Height));
container.ScrollOffset = new XPoint(0, scrollOffset);
container.PerformPaint(g);
}
scrollOffset -= pageSize.Height;
}
if (config.AddPageCountFoooter && document.PageCount > 1) //Only add page numbers if more than one page
{
AddPageCountFoooter(document, pageSize);
}
// SL: Set config option to handle links or not as it crashes for
// some valid html links.
// TODO: Investigate reason for crashing.
if (config.HandleLinks)
{
HandleLinks(document, container, orgPageSize, pageSize);
}
}
}
}
private static void AddGridCols(CssData expected, params int[] gridCols)
{
var val = string.Join(' ', gridCols.Select(x => Style.Properties.Utils.TwipsToCm(x) + "cm"));
expected.AddAttribute(".demo", "grid-template-columns", val);
}
public void InsertCss(CssPropertiesSet other, CssData cssData)
{
cssData.AddRange(_cssData);
}
/// <summary>
/// Renders the specified HTML into a new image of unknown size that will be determined by min/max width/height and HTML layout.<br/>
/// If <paramref name="maxSize.Width"/> is zero the html will use all the required width, otherwise it will perform line
/// wrap as specified in the html<br/>
/// If <paramref name="maxSize.Height"/> is zero the html will use all the required height, otherwise it will clip at the
/// given max height not rendering the html below it.<br/>
/// If <paramref name="minSize"/> (Width/Height) is above zero the rendered image will not be smaller than the given min size.<br/>
/// The generated image have transparent background that the html is rendered on.<br/>
/// GDI+ text rending can be controlled by providing <see cref="TextRenderingHint"/>.<br/>
/// See "Rendering to image" remarks section on <see cref="HtmlRender"/>.<br/>
/// </summary>
/// <param name="html">HTML source to render</param>
/// <param name="minSize">optional: the min size of the rendered html (zero - not limit the width/height)</param>
/// <param name="maxSize">optional: the max size of the rendered html, if not zero and html cannot be layout within the limit it will be clipped (zero - not limit the width/height)</param>
/// <param name="textRenderingHint">optional: (default - SingleBitPerPixelGridFit)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
public static Image RenderToImageGdiPlus(string html, Size minSize, Size maxSize, TextRenderingHint textRenderingHint = TextRenderingHint.AntiAlias, CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
if (string.IsNullOrEmpty(html))
{
return(new Bitmap(0, 0, PixelFormat.Format32bppArgb));
}
using (var container = new HtmlContainer())
{
container.AvoidAsyncImagesLoading = true;
container.AvoidImagesLateLoading = true;
container.UseGdiPlusTextRendering = true;
if (stylesheetLoad != null)
{
container.StylesheetLoad += stylesheetLoad;
}
if (imageLoad != null)
{
container.ImageLoad += imageLoad;
}
container.SetHtml(html, cssData);
var finalSize = MeasureHtmlByRestrictions(container, minSize, maxSize);
container.MaxSize = finalSize;
// create the final image to render into by measured size
var image = new Bitmap(finalSize.Width, finalSize.Height, PixelFormat.Format32bppArgb);
// render HTML into the image
using (var g = Graphics.FromImage(image))
{
g.TextRenderingHint = textRenderingHint;
container.PerformPaint(g);
}
return(image);
}
}
/// <summary>
/// Applies style to all boxes in the tree.<br/>
/// If the html tag has style defined for each apply that style to the css box of the tag.<br/>
/// If the html tag has "class" attribute and the class name has style defined apply that style on the tag css box.<br/>
/// If the html tag has "style" attribute parse it and apply the parsed style on the tag css box.<br/>
/// </summary>
/// <param name="box">the box to apply the style to</param>
/// <param name="cssData">the style data for the html</param>
private void CascadeApplyStyles(CssBox box, CssData cssData)
{
box.InheritStyle();
if (box.HtmlTag != null)
{
// try assign style using all wildcard
AssignCssBlocks(box, cssData, "*");
// try assign style using the html element tag
AssignCssBlocks(box, cssData, box.HtmlTag.Name);
// try assign style using the "class" attribute of the html element
if (box.HtmlTag.HasAttribute("class"))
{
AssignClassCssBlocks(box, cssData);
}
// try assign style using the "id" attribute of the html element
if (box.HtmlTag.HasAttribute("id"))
{
var id = box.HtmlTag.TryGetAttribute("id");
AssignCssBlocks(box, cssData, "#" + id);
}
TranslateAttributes(box.HtmlTag, box);
// Check for the style="" attribute
if (box.HtmlTag.HasAttribute("style"))
{
var block = _cssParser.ParseCssBlock(box.HtmlTag.Name, box.HtmlTag.TryGetAttribute("style"));
if (block != null)
AssignCssBlock(box, block);
}
}
// cascade text decoration only to boxes that actually have text so it will be handled correctly.
if (box.TextDecoration != String.Empty && box.Text == null)
{
foreach (var childBox in box.Boxes)
childBox.TextDecoration = box.TextDecoration;
box.TextDecoration = string.Empty;
}
foreach (var childBox in box.Boxes)
{
CascadeApplyStyles(childBox, cssData);
}
}
/// <summary>
/// Renders the specified HTML source on the specified location and max size restriction.<br/>
/// If <paramref name="maxSize"/>.Width is zero the html will use all the required width, otherwise it will perform line
/// wrap as specified in the html<br/>
/// If <paramref name="maxSize"/>.Height is zero the html will use all the required height, otherwise it will clip at the
/// given max height not rendering the html below it.<br/>
/// Returned is the actual width and height of the rendered html.<br/>
/// </summary>
/// <param name="g">Device to render with</param>
/// <param name="html">HTML source to render</param>
/// <param name="location">the top-left most location to start render the html at</param>
/// <param name="maxSize">the max size of the rendered html (if height above zero it will be clipped)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="useGdiPlusTextRendering">true - use GDI+ text rendering, false - use GDI text rendering</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the actual size of the rendered html</returns>
private static SizeF RenderHtml(Graphics g, string html, PointF location, SizeF maxSize, CssData cssData, bool useGdiPlusTextRendering, EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad, EventHandler <HtmlImageLoadEventArgs> imageLoad)
{
SizeF actualSize = SizeF.Empty;
if (!string.IsNullOrEmpty(html))
{
using (var container = new HtmlContainer())
{
container.Location = location;
container.MaxSize = maxSize;
container.AvoidAsyncImagesLoading = true;
container.AvoidImagesLateLoading = true;
container.UseGdiPlusTextRendering = useGdiPlusTextRendering;
if (stylesheetLoad != null)
{
container.StylesheetLoad += stylesheetLoad;
}
if (imageLoad != null)
{
container.ImageLoad += imageLoad;
}
container.SetHtml(html, cssData);
container.PerformLayout(g);
container.PerformPaint(g);
actualSize = container.ActualSize;
}
}
return(actualSize);
}
/// <summary>
/// Create PDF document from given HTML.<br/>
/// </summary>
/// <param name="html">HTML source to create PDF from</param>
/// <param name="pageSize">the page size to use for each page in the generated pdf </param>
/// <param name="margin">the margin to use between the HTML and the edges of each page</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
public static PdfDocument GeneratePdf(string html, PageSize pageSize, int margin = 20, CssData cssData = null, EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
var config = new PdfGenerateConfig();
config.PageSize = pageSize;
config.SetMargins(margin);
return(GeneratePdf(html, config, cssData, stylesheetLoad, imageLoad));
}
public override void SetOn(CssData data)
{
data.AddAttribute(Selector, "display", "none!important");
}
/// <summary>
/// Renders the specified HTML into a new image of unknown size that will be determined by max width/height and HTML layout.<br/>
/// If <paramref name="maxWidth"/> is zero the html will use all the required width, otherwise it will perform line
/// wrap as specified in the html<br/>
/// If <paramref name="maxHeight"/> is zero the html will use all the required height, otherwise it will clip at the
/// given max height not rendering the html below it.<br/>
/// The generated image have transparent background that the html is rendered on.<br/>
/// GDI+ text rending can be controlled by providing <see cref="TextRenderingHint"/>.<br/>
/// See "Rendering to image" remarks section on <see cref="HtmlRender"/>.<br/>
/// </summary>
/// <param name="html">HTML source to render</param>
/// <param name="maxWidth">optional: the max width of the rendered html, if not zero and html cannot be layout within the limit it will be clipped</param>
/// <param name="maxHeight">optional: the max height of the rendered html, if not zero and html cannot be layout within the limit it will be clipped</param>
/// <param name="textRenderingHint">optional: (default - SingleBitPerPixelGridFit)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
public static Image RenderToImageGdiPlus(string html, int maxWidth = 0, int maxHeight = 0, TextRenderingHint textRenderingHint = TextRenderingHint.AntiAlias, CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
return(RenderToImageGdiPlus(html, Size.Empty, new Size(maxWidth, maxHeight), textRenderingHint, cssData, stylesheetLoad, imageLoad));
}
/// <summary>
/// Create PDF pages from given HTML and appends them to the provided PDF document.<br/>
/// </summary>
/// <param name="document">PDF document to append pages to</param>
/// <param name="html">HTML source to create PDF from</param>
/// <param name="pageSize">the page size to use for each page in the generated pdf </param>
/// <param name="margin">the margin to use between the HTML and the edges of each page</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
public static void AddPdfPages(PdfDocument document, string html, PageSize pageSize, int margin = 20, CssData cssData = null, EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
var config = new PdfGenerateConfig();
config.PageSize = pageSize;
config.SetMargins(margin);
AddPdfPages(document, html, config, cssData, stylesheetLoad, imageLoad);
}
/// <summary>
/// Renders the specified HTML source on the specified location and max size restriction.<br/>
/// If <paramref name="maxSize"/>.Width is zero the html will use all the required width, otherwise it will perform line
/// wrap as specified in the html<br/>
/// If <paramref name="maxSize"/>.Height is zero the html will use all the required height, otherwise it will clip at the
/// given max height not rendering the html below it.<br/>
/// Clip the graphics so the html will not be rendered outside the max height bound given.<br/>
/// Returned is the actual width and height of the rendered html.<br/>
/// </summary>
/// <param name="g">Device to render with</param>
/// <param name="html">HTML source to render</param>
/// <param name="location">the top-left most location to start render the html at</param>
/// <param name="maxSize">the max size of the rendered html (if height above zero it will be clipped)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="useGdiPlusTextRendering">true - use GDI+ text rendering, false - use GDI text rendering</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the actual size of the rendered html</returns>
private static SizeF RenderClip(Graphics g, string html, PointF location, SizeF maxSize, CssData cssData, bool useGdiPlusTextRendering, EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad, EventHandler <HtmlImageLoadEventArgs> imageLoad)
{
Region prevClip = null;
if (maxSize.Height > 0)
{
prevClip = g.Clip;
g.SetClip(new RectangleF(location, maxSize));
}
var actualSize = RenderHtml(g, html, location, maxSize, cssData, useGdiPlusTextRendering, stylesheetLoad, imageLoad);
if (prevClip != null)
{
g.SetClip(prevClip, CombineMode.Replace);
}
return(actualSize);
}
public static Metafile RenderToMetafile(string html, float left = 0, float top = 0, float maxWidth = 0, CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
Metafile image;
IntPtr dib;
var memoryHdc = Win32Utils.CreateMemoryHdc(IntPtr.Zero, 1, 1, out dib);
try
{
image = new Metafile(memoryHdc, EmfType.EmfPlusDual, "..");
using (var g = Graphics.FromImage(image))
{
Render(g, html, left, top, maxWidth, cssData, stylesheetLoad, imageLoad);
}
}
finally
{
Win32Utils.ReleaseMemoryHdc(memoryHdc, dib);
}
return(image);
}
/// <summary>
/// LoadFromRaw stylesheet data from the given source.<br/>
/// The source can be local file or web URI.<br/>
/// First raise <see cref="HtmlStylesheetLoadEventArgs"/> event to allow the client to overwrite the stylesheet loading.<br/>
/// If the stylesheet is downloaded from URI we will try to correct local URIs to absolute.<br/>
/// </summary>
/// <param name="htmlContainer">the container of the html to handle load stylesheet for</param>
/// <param name="src">the source of the element to load the stylesheet by</param>
/// <param name="attributes">the attributes of the link element</param>
/// <param name="stylesheet">return the stylesheet string that has been loaded (null if failed or <paramref name="stylesheetData"/> is given)</param>
/// <param name="stylesheetData">return stylesheet data object that was provided by overwrite (null if failed or <paramref name="stylesheet"/> is given)</param>
public static void LoadStylesheet(HtmlContainerInt htmlContainer, string src, Dictionary <string, string> attributes, out string stylesheet, out CssData stylesheetData)
{
ArgChecker.AssertArgNotNull(htmlContainer, "htmlContainer");
stylesheet = null;
stylesheetData = null;
try
{
var args = new HtmlStylesheetLoadEventArgs(src, attributes);
htmlContainer.RaiseHtmlStylesheetLoadEvent(args);
if (!string.IsNullOrEmpty(args.SetStyleSheet))
{
stylesheet = args.SetStyleSheet;
}
else if (args.SetStyleSheetData != null)
{
stylesheetData = args.SetStyleSheetData;
}
else if (args.SetSrc != null)
{
stylesheet = LoadStylesheet(htmlContainer, args.SetSrc);
}
else
{
stylesheet = LoadStylesheet(htmlContainer, src);
}
}
catch (Exception ex)
{
htmlContainer.ReportError(HtmlRenderErrorType.CssParsing, "Exception in handling stylesheet source", ex);
}
}
/// <summary>
/// Parse the given stylesheet to <see cref="CssData"/> object.<br/>
/// If <paramref name="combineWithDefault"/> is true the parsed css blocks are added to the
/// default css data (as defined by W3), merged if class name already exists. If false only the data in the given stylesheet is returned.
/// </summary>
/// <seealso cref="http://www.w3.org/TR/CSS21/sample.html"/>
/// <param name="stylesheet">the stylesheet source to parse</param>
/// <param name="combineWithDefault">true - combine the parsed css data with default css data, false - return only the parsed css data</param>
/// <returns>the parsed css data</returns>
public static CssData ParseStyleSheet(string stylesheet, bool combineWithDefault = true)
{
return(CssData.Parse(WinFormsAdapter.Instance, stylesheet, combineWithDefault));
}
/// <summary>
/// Applies style to all boxes in the tree.<br/>
/// If the html tag has style defined for each apply that style to the css box of the tag.<br/>
/// If the html tag has "class" attribute and the class name has style defined apply that style on the tag css box.<br/>
/// If the html tag has "style" attribute parse it and apply the parsed style on the tag css box.<br/>
/// If the html tag is "style" tag parse it content and add to the css data for all future tags parsing.<br/>
/// If the html tag is "link" that point to style data parse it content and add to the css data for all future tags parsing.<br/>
/// </summary>
/// <param name="box"></param>
/// <param name="htmlContainer">the html container to use for reference resolve</param>
/// <param name="cssData"> </param>
/// <param name="cssDataChanged">check if the css data has been modified by the handled html not to change the base css data</param>
private static void CascadeStyles(CssBox box, HtmlContainer htmlContainer, ref CssData cssData, ref bool cssDataChanged)
{
box.InheritStyle();
if (box.HtmlTag != null)
{
// try assign style using the html element tag
AssignCssBlocks(box, cssData, box.HtmlTag.Name);
// try assign style using the "class" attribute of the html element
if (box.HtmlTag.HasAttribute("class"))
{
AssignClassCssBlocks(box, cssData);
}
// try assign style using the "id" attribute of the html element
if (box.HtmlTag.HasAttribute("id"))
{
var id = box.HtmlTag.TryGetAttribute("id");
AssignCssBlocks(box, cssData, "#" + id);
}
TranslateAttributes(box.HtmlTag, box);
// Check for the style="" attribute
if (box.HtmlTag.HasAttribute("style"))
{
var block = CssParser.ParseCssBlock(box.HtmlTag.Name, box.HtmlTag.TryGetAttribute("style"));
AssignCssBlock(box, block);
}
// Check for the <style> tag
if (box.HtmlTag.Name.Equals("style", StringComparison.CurrentCultureIgnoreCase) && box.Boxes.Count == 1)
{
CloneCssData(ref cssData, ref cssDataChanged);
CssParser.ParseStyleSheet(cssData, box.Boxes[0].Text.CutSubstring());
}
// Check for the <link rel=stylesheet> tag
if (box.HtmlTag.Name.Equals("link", StringComparison.CurrentCultureIgnoreCase) &&
box.GetAttribute("rel", string.Empty).Equals("stylesheet", StringComparison.CurrentCultureIgnoreCase))
{
CloneCssData(ref cssData, ref cssDataChanged);
var styleSheet = StylesheetLoadHelper.LoadStylesheet(htmlContainer, box.GetAttribute("href", string.Empty), box.HtmlTag.Attributes);
CssParser.ParseStyleSheet(cssData, styleSheet);
}
}
// cascade text decoration only to boxes that actually have text so it will be handled correctly.
if (box.TextDecoration != String.Empty && box.Text == null)
{
foreach (var childBox in box.Boxes)
childBox.TextDecoration = box.TextDecoration;
box.TextDecoration = string.Empty;
}
foreach (var childBox in box.Boxes)
{
CascadeStyles(childBox, htmlContainer, ref cssData, ref cssDataChanged);
}
}
/// <summary>
/// Measure the size (width and height) required to draw the given html under given max width restriction.<br/>
/// If no max width restriction is given the layout will use the maximum possible width required by the content,
/// it can be the longest text line or full image width.<br/>
/// Use GDI+ text rending, use <see cref="Graphics.TextRenderingHint"/> to control text rendering.
/// </summary>
/// <param name="g">Device to use for measure</param>
/// <param name="html">HTML source to render</param>
/// <param name="maxWidth">optional: bound the width of the html to render in (default - 0, unlimited)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the size required for the html</returns>
public static SizeF MeasureGdiPlus(Graphics g, string html, float maxWidth = 0, CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
ArgChecker.AssertArgNotNull(g, "g");
return(Measure(g, html, maxWidth, cssData, true, stylesheetLoad, imageLoad));
}
/// <summary>
/// Write stylesheet data inline into the html.
/// </summary>
/// <param name="sb">the string builder to write stylesheet into</param>
/// <param name="cssData">the css data to write to the head</param>
/// <param name="indent">the indent to use for nice formating</param>
private static void WriteStylesheet(StringBuilder sb, CssData cssData, int indent)
{
sb.Append(new string(' ', indent * 4));
sb.AppendLine("<style type=\"text/css\">");
foreach (var cssBlocks in cssData.MediaBlocks["all"])
{
sb.Append(new string(' ', (indent + 1) * 4));
sb.Append(cssBlocks.Key);
sb.Append(" { ");
foreach (var cssBlock in cssBlocks.Value)
{
foreach (var property in cssBlock.Properties)
{
// atodo: handle selectors
sb.AppendFormat("{0}: {1};", property.Key, property.Value);
}
}
sb.Append(" }");
sb.AppendLine();
}
sb.Append(new string(' ', indent * 4));
sb.AppendLine("</style>");
}
/// <summary>
/// Renders the specified HTML source on the specified location and max size restriction.<br/>
/// Use GDI+ text rending, use <see cref="Graphics.TextRenderingHint"/> to control text rendering.<br/>
/// If <paramref name="maxWidth"/> is zero the html will use all the required width, otherwise it will perform line
/// wrap as specified in the html<br/>
/// Returned is the actual width and height of the rendered html.<br/>
/// </summary>
/// <param name="g">Device to render with</param>
/// <param name="html">HTML source to render</param>
/// <param name="left">optional: the left most location to start render the html at (default - 0)</param>
/// <param name="top">optional: the top most location to start render the html at (default - 0)</param>
/// <param name="maxWidth">optional: bound the width of the html to render in (default - 0, unlimited)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the actual size of the rendered html</returns>
public static SizeF RenderGdiPlus(Graphics g, string html, float left = 0, float top = 0, float maxWidth = 0, CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
ArgChecker.AssertArgNotNull(g, "g");
return(RenderClip(g, html, new PointF(left, top), new SizeF(maxWidth, 0), cssData, true, stylesheetLoad, imageLoad));
}
/// <summary>
/// Feeds the style with a block about the specific media.<br/>
/// When no media is specified, "all" will be used.
/// </summary>
/// <param name="cssData"> </param>
/// <param name="block">the CSS block to handle</param>
/// <param name="media">optional: the media (default - all)</param>
private void FeedStyleBlock(CssData cssData, string block, string media = "all")
{
int startIdx = block.IndexOf("{", StringComparison.Ordinal);
int endIdx = startIdx > -1 ? block.IndexOf("}", startIdx) : -1;
if (startIdx > -1 && endIdx > -1)
{
string blockSource = block.Substring(startIdx + 1, endIdx - startIdx - 1);
var classes = block.Substring(0, startIdx).Split(',');
foreach (string cls in classes)
{
string className = cls.Trim(_cssClassTrimChars);
if (!String.IsNullOrEmpty(className))
{
var newblock = ParseCssBlockImp(className, blockSource);
if (newblock != null)
{
cssData.AddCssBlock(media, newblock);
}
}
}
}
}
/// <summary>
/// Renders the specified HTML source on the specified location and max size restriction.<br/>
/// Use GDI+ text rending, use <see cref="Graphics.TextRenderingHint"/> to control text rendering.<br/>
/// If <paramref name="maxSize"/>.Width is zero the html will use all the required width, otherwise it will perform line
/// wrap as specified in the html<br/>
/// If <paramref name="maxSize"/>.Height is zero the html will use all the required height, otherwise it will clip at the
/// given max height not rendering the html below it.<br/>
/// Returned is the actual width and height of the rendered html.<br/>
/// </summary>
/// <param name="g">Device to render with</param>
/// <param name="html">HTML source to render</param>
/// <param name="location">the top-left most location to start render the html at</param>
/// <param name="maxSize">the max size of the rendered html (if height above zero it will be clipped)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the actual size of the rendered html</returns>
public static SizeF RenderGdiPlus(Graphics g, string html, PointF location, SizeF maxSize, CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
ArgChecker.AssertArgNotNull(g, "g");
return(RenderClip(g, html, location, maxSize, cssData, true, stylesheetLoad, imageLoad));
}
/// <summary>
/// Parse given stylesheet for CSS blocks<br/>
/// This blocks are added under the "all" keyword.
/// </summary>
/// <param name="cssData">the CSS data to fill with parsed CSS objects</param>
/// <param name="stylesheet">the stylesheet to parse</param>
private void ParseStyleBlocks(CssData cssData, string stylesheet)
{
var startIdx = 0;
int endIdx = 0;
while (startIdx < stylesheet.Length && endIdx > -1)
{
endIdx = startIdx;
while (endIdx + 1 < stylesheet.Length)
{
endIdx++;
if (stylesheet[endIdx] == '}')
startIdx = endIdx + 1;
if (stylesheet[endIdx] == '{')
break;
}
int midIdx = endIdx + 1;
if (endIdx > -1)
{
endIdx++;
while (endIdx < stylesheet.Length)
{
if (stylesheet[endIdx] == '{')
startIdx = midIdx + 1;
if (stylesheet[endIdx] == '}')
break;
endIdx++;
}
if (endIdx < stylesheet.Length)
{
while (Char.IsWhiteSpace(stylesheet[startIdx]))
startIdx++;
var substring = stylesheet.Substring(startIdx, endIdx - startIdx + 1);
FeedStyleBlock(cssData, substring);
}
startIdx = endIdx + 1;
}
}
}
/// <summary>
/// Renders the specified HTML on top of the given image.<br/>
/// <paramref name="image"/> will contain the rendered html in it on top of original content.<br/>
/// <paramref name="image"/> must not contain transparent pixels as it will corrupt the rendered html text.<br/>
/// The HTML will be layout by the given image size but may be clipped if cannot fit.<br/>
/// See "Rendering to image" remarks section on <see cref="HtmlRender"/>.<br/>
/// </summary>
/// <param name="image">the image to render the html on</param>
/// <param name="html">HTML source to render</param>
/// <param name="location">optional: the top-left most location to start render the html at (default - 0,0)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
public static void RenderToImage(Image image, string html, PointF location = new PointF(), CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
ArgChecker.AssertArgNotNull(image, "image");
var maxSize = new SizeF(image.Size.Width - location.X, image.Size.Height - location.Y);
RenderToImage(image, html, location, maxSize, cssData, stylesheetLoad, imageLoad);
}
/// <summary>
/// Applies style to all boxes in the tree.<br/>
/// If the html tag has style defined for each apply that style to the css box of the tag.<br/>
/// If the html tag has "class" attribute and the class name has style defined apply that style on the tag css box.<br/>
/// If the html tag has "style" attribute parse it and apply the parsed style on the tag css box.<br/>
/// If the html tag is "style" tag parse it content and add to the css data for all future tags parsing.<br/>
/// If the html tag is "link" that point to style data parse it content and add to the css data for all future tags parsing.<br/>
/// </summary>
/// <param name="box"></param>
/// <param name="bridge"> </param>
/// <param name="cssData"> </param>
/// <param name="cssDataChanged">check if the css data has been modified by the handled html not to change the base css data</param>
private static void CascadeStyles(CssBox box, object bridge, ref CssData cssData, ref bool cssDataChanged)
{
box.InheritStyle();
if (box.HtmlTag != null)
{
// try assign style using the html element tag
AssignCssBlocks(box, cssData, box.HtmlTag.Name);
// try assign style using the "class" attribute of the html element
if (box.HtmlTag.HasAttribute("class"))
{
AssignCssBlocks(box, cssData, "." + box.HtmlTag.Attributes["class"]);
AssignCssBlocks(box, cssData, box.HtmlTag.Name + "." + box.HtmlTag.Attributes["class"]);
}
// try assign style using the "id" attribute of the html element
if (box.HtmlTag.HasAttribute("id"))
{
AssignCssBlocks(box, cssData, "#" + box.HtmlTag.Attributes["id"]);
}
HtmlParser.TranslateAttributes(box.HtmlTag, box);
// Check for the style="" attribute
if (box.HtmlTag.HasAttribute("style"))
{
var block = CssParser.ParseCssBlockImp(box.HtmlTag.Name, box.HtmlTag.Attributes["style"]);
AssignCssBlock(box, block);
}
// Check for the <style> tag
if (box.HtmlTag.Name.Equals("style", StringComparison.CurrentCultureIgnoreCase) && box.Boxes.Count == 1)
{
CloneCssData(ref cssData, ref cssDataChanged);
CssParser.ParseStyleSheet(cssData, box.Boxes[0].Text);
}
// Check for the <link rel=stylesheet> tag
if (box.HtmlTag.Name.Equals("link", StringComparison.CurrentCultureIgnoreCase) &&
box.GetAttribute("rel", string.Empty).Equals("stylesheet", StringComparison.CurrentCultureIgnoreCase))
{
CloneCssData(ref cssData, ref cssDataChanged);
var styleSheet = CssValueParser.GetStyleSheet(box.GetAttribute("href", string.Empty), bridge);
CssParser.ParseStyleSheet(cssData, styleSheet);
}
}
foreach (var childBox in box.Boxes)
{
CascadeStyles(childBox, bridge, ref cssData, ref cssDataChanged);
}
}
/// <summary>
/// Renders the specified HTML on top of the given image.<br/>
/// <paramref name="image"/> will contain the rendered html in it on top of original content.<br/>
/// <paramref name="image"/> must not contain transparent pixels as it will corrupt the rendered html text.<br/>
/// See "Rendering to image" remarks section on <see cref="HtmlRender"/>.<br/>
/// </summary>
/// <param name="image">the image to render the html on</param>
/// <param name="html">HTML source to render</param>
/// <param name="location">the top-left most location to start render the html at</param>
/// <param name="maxSize">the max size of the rendered html (if height above zero it will be clipped)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
public static void RenderToImage(Image image, string html, PointF location, SizeF maxSize, CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
ArgChecker.AssertArgNotNull(image, "image");
if (!string.IsNullOrEmpty(html))
{
// create memory buffer from desktop handle that supports alpha channel
IntPtr dib;
var memoryHdc = Win32Utils.CreateMemoryHdc(IntPtr.Zero, image.Width, image.Height, out dib);
try
{
// create memory buffer graphics to use for HTML rendering
using (var memoryGraphics = Graphics.FromHdc(memoryHdc))
{
// draw the image to the memory buffer to be the background of the rendered html
memoryGraphics.DrawImageUnscaled(image, 0, 0);
// render HTML into the memory buffer
RenderHtml(memoryGraphics, html, location, maxSize, cssData, false, stylesheetLoad, imageLoad);
}
// copy from memory buffer to image
CopyBufferToImage(memoryHdc, image);
}
finally
{
Win32Utils.ReleaseMemoryHdc(memoryHdc, dib);
}
}
}
/// <summary>
/// Renders the specified HTML into a new image of the requested size.<br/>
/// The HTML will be layout by the given size but will be clipped if cannot fit.<br/>
/// <p>
/// Limitation: The image cannot have transparent background, by default it will be white.<br/>
/// See "Rendering to image" remarks section on <see cref="HtmlRender"/>.<br/>
/// </p>
/// </summary>
/// <param name="html">HTML source to render</param>
/// <param name="size">The size of the image to render into, layout html by width and clipped by height</param>
/// <param name="backgroundColor">optional: the color to fill the image with (default - white)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
/// <exception cref="ArgumentOutOfRangeException">if <paramref name="backgroundColor"/> is <see cref="Color.Transparent"/></exception>.
public static Image RenderToImage(string html, Size size, Color backgroundColor = new Color(), CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
if (backgroundColor == Color.Transparent)
{
throw new ArgumentOutOfRangeException("backgroundColor", "Transparent background in not supported");
}
// create the final image to render into
var image = new Bitmap(size.Width, size.Height, PixelFormat.Format32bppArgb);
if (!string.IsNullOrEmpty(html))
{
// create memory buffer from desktop handle that supports alpha channel
IntPtr dib;
var memoryHdc = Win32Utils.CreateMemoryHdc(IntPtr.Zero, image.Width, image.Height, out dib);
try
{
// create memory buffer graphics to use for HTML rendering
using (var memoryGraphics = Graphics.FromHdc(memoryHdc))
{
memoryGraphics.Clear(backgroundColor != Color.Empty ? backgroundColor : Color.White);
// render HTML into the memory buffer
RenderHtml(memoryGraphics, html, PointF.Empty, size, cssData, true, stylesheetLoad, imageLoad);
}
// copy from memory buffer to image
CopyBufferToImage(memoryHdc, image);
}
finally
{
Win32Utils.ReleaseMemoryHdc(memoryHdc, dib);
}
}
return(image);
}
/// <summary>
/// Renders the specified HTML into a new image of unknown size that will be determined by max width/height and HTML layout.<br/>
/// If <paramref name="maxWidth"/> is zero the html will use all the required width, otherwise it will perform line
/// wrap as specified in the html<br/>
/// If <paramref name="maxHeight"/> is zero the html will use all the required height, otherwise it will clip at the
/// given max height not rendering the html below it.<br/>
/// <p>
/// Limitation: The image cannot have transparent background, by default it will be white.<br/>
/// See "Rendering to image" remarks section on <see cref="HtmlRender"/>.<br/>
/// </p>
/// </summary>
/// <param name="html">HTML source to render</param>
/// <param name="maxWidth">optional: the max width of the rendered html, if not zero and html cannot be layout within the limit it will be clipped</param>
/// <param name="maxHeight">optional: the max height of the rendered html, if not zero and html cannot be layout within the limit it will be clipped</param>
/// <param name="backgroundColor">optional: the color to fill the image with (default - white)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
/// <exception cref="ArgumentOutOfRangeException">if <paramref name="backgroundColor"/> is <see cref="Color.Transparent"/></exception>.
public static Image RenderToImage(string html, int maxWidth = 0, int maxHeight = 0, Color backgroundColor = new Color(), CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
return(RenderToImage(html, Size.Empty, new Size(maxWidth, maxHeight), backgroundColor, cssData, stylesheetLoad, imageLoad));
}
/// <summary>
/// Set the selected text style (selection text color and background color).
/// </summary>
/// <param name="htmlContainer"> </param>
/// <param name="cssData">the style data</param>
private void SetTextSelectionStyle(HtmlContainerInt htmlContainer, CssData cssData)
{
htmlContainer.SelectionForeColor = RColor.Empty;
htmlContainer.SelectionBackColor = RColor.Empty;
if (cssData.ContainsCssBlock("::selection"))
{
var blocks = cssData.GetCssBlock("::selection");
foreach (var block in blocks)
{
if (block.Properties.ContainsKey("color"))
htmlContainer.SelectionForeColor = _cssParser.ParseColor(block.Properties["color"]);
if (block.Properties.ContainsKey("background-color"))
htmlContainer.SelectionBackColor = _cssParser.ParseColor(block.Properties["background-color"]);
}
}
}
/// <summary>
/// Renders the specified HTML into a new image of unknown size that will be determined by min/max width/height and HTML layout.<br/>
/// If <paramref name="maxSize.Width"/> is zero the html will use all the required width, otherwise it will perform line
/// wrap as specified in the html<br/>
/// If <paramref name="maxSize.Height"/> is zero the html will use all the required height, otherwise it will clip at the
/// given max height not rendering the html below it.<br/>
/// If <paramref name="minSize"/> (Width/Height) is above zero the rendered image will not be smaller than the given min size.<br/>
/// <p>
/// Limitation: The image cannot have transparent background, by default it will be white.<br/>
/// See "Rendering to image" remarks section on <see cref="HtmlRender"/>.<br/>
/// </p>
/// </summary>
/// <param name="html">HTML source to render</param>
/// <param name="minSize">optional: the min size of the rendered html (zero - not limit the width/height)</param>
/// <param name="maxSize">optional: the max size of the rendered html, if not zero and html cannot be layout within the limit it will be clipped (zero - not limit the width/height)</param>
/// <param name="backgroundColor">optional: the color to fill the image with (default - white)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
/// <exception cref="ArgumentOutOfRangeException">if <paramref name="backgroundColor"/> is <see cref="Color.Transparent"/></exception>.
public static Image RenderToImage(string html, Size minSize, Size maxSize, Color backgroundColor = new Color(), CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
if (backgroundColor == Color.Transparent)
{
throw new ArgumentOutOfRangeException("backgroundColor", "Transparent background in not supported");
}
if (string.IsNullOrEmpty(html))
{
return(new Bitmap(0, 0, PixelFormat.Format32bppArgb));
}
using (var container = new HtmlContainer())
{
container.AvoidAsyncImagesLoading = true;
container.AvoidImagesLateLoading = true;
if (stylesheetLoad != null)
{
container.StylesheetLoad += stylesheetLoad;
}
if (imageLoad != null)
{
container.ImageLoad += imageLoad;
}
container.SetHtml(html, cssData);
var finalSize = MeasureHtmlByRestrictions(container, minSize, maxSize);
container.MaxSize = finalSize;
// create the final image to render into by measured size
var image = new Bitmap(finalSize.Width, finalSize.Height, PixelFormat.Format32bppArgb);
// create memory buffer from desktop handle that supports alpha channel
IntPtr dib;
var memoryHdc = Win32Utils.CreateMemoryHdc(IntPtr.Zero, image.Width, image.Height, out dib);
try
{
// render HTML into the memory buffer
using (var memoryGraphics = Graphics.FromHdc(memoryHdc))
{
memoryGraphics.Clear(backgroundColor != Color.Empty ? backgroundColor : Color.White);
container.PerformPaint(memoryGraphics);
}
// copy from memory buffer to image
CopyBufferToImage(memoryHdc, image);
}
finally
{
Win32Utils.ReleaseMemoryHdc(memoryHdc, dib);
}
return(image);
}
}
/// <summary>
/// Clone css data if it has not already been cloned.<br/>
/// Used to preserve the base css data used when changed by style inside html.
/// </summary>
private static void CloneCssData(ref CssData cssData, ref bool cssDataChanged)
{
if (!cssDataChanged)
{
cssDataChanged = true;
cssData = cssData.Clone();
}
}
/// <summary>
/// Renders the specified HTML into a new image of the requested size.<br/>
/// The HTML will be layout by the given size but will be clipped if cannot fit.<br/>
/// The generated image have transparent background that the html is rendered on.<br/>
/// GDI+ text rending can be controlled by providing <see cref="TextRenderingHint"/>.<br/>
/// See "Rendering to image" remarks section on <see cref="HtmlRender"/>.<br/>
/// </summary>
/// <param name="html">HTML source to render</param>
/// <param name="size">The size of the image to render into, layout html by width and clipped by height</param>
/// <param name="textRenderingHint">optional: (default - SingleBitPerPixelGridFit)</param>
/// <param name="cssData">optional: the style to use for html rendering (default - use W3 default style)</param>
/// <param name="stylesheetLoad">optional: can be used to overwrite stylesheet resolution logic</param>
/// <param name="imageLoad">optional: can be used to overwrite image resolution logic</param>
/// <returns>the generated image of the html</returns>
public static Image RenderToImageGdiPlus(string html, Size size, TextRenderingHint textRenderingHint = TextRenderingHint.AntiAlias, CssData cssData = null,
EventHandler <HtmlStylesheetLoadEventArgs> stylesheetLoad = null, EventHandler <HtmlImageLoadEventArgs> imageLoad = null)
{
var image = new Bitmap(size.Width, size.Height, PixelFormat.Format32bppArgb);
using (var g = Graphics.FromImage(image))
{
g.TextRenderingHint = textRenderingHint;
RenderHtml(g, html, PointF.Empty, size, cssData, true, stylesheetLoad, imageLoad);
}
return(image);
}
/// <summary>
/// Read styles defined inside the dom structure in links and style elements.<br/>
/// If the html tag is "style" tag parse it content and add to the css data for all future tags parsing.<br/>
/// If the html tag is "link" that point to style data parse it content and add to the css data for all future tags parsing.<br/>
/// </summary>
/// <param name="box">the box to parse style data in</param>
/// <param name="htmlContainer">the html container to use for reference resolve</param>
/// <param name="cssData">the style data to fill with found styles</param>
/// <param name="cssDataChanged">check if the css data has been modified by the handled html not to change the base css data</param>
private void CascadeParseStyles(CssBox box, HtmlContainerInt htmlContainer, ref CssData cssData, ref bool cssDataChanged)
{
if (box.HtmlTag != null)
{
// Check for the <link rel=stylesheet> tag
if (box.HtmlTag.Name.Equals("link", StringComparison.CurrentCultureIgnoreCase) &&
box.GetAttribute("rel", string.Empty).Equals("stylesheet", StringComparison.CurrentCultureIgnoreCase))
{
CloneCssData(ref cssData, ref cssDataChanged);
string stylesheet;
CssData stylesheetData;
StylesheetLoadHandler.LoadStylesheet(htmlContainer, box.GetAttribute("href", string.Empty), box.HtmlTag.Attributes, out stylesheet, out stylesheetData);
if (stylesheet != null)
_cssParser.ParseStyleSheet(cssData, stylesheet);
else if (stylesheetData != null)
cssData.Combine(stylesheetData);
}
// Check for the <style> tag
if (box.HtmlTag.Name.Equals("style", StringComparison.CurrentCultureIgnoreCase) && box.Boxes.Count > 0)
{
CloneCssData(ref cssData, ref cssDataChanged);
foreach (var child in box.Boxes)
_cssParser.ParseStyleSheet(cssData, child.Text.CutSubstring());
}
}
foreach (var childBox in box.Boxes)
{
CascadeParseStyles(childBox, htmlContainer, ref cssData, ref cssDataChanged);
}
}
/// <summary>
/// Generate css tree by parsing the given html and applying the given css style data on it.
/// </summary>
/// <param name="html">the html to parse</param>
/// <param name="htmlContainer">the html container to use for reference resolve</param>
/// <param name="cssData">the css data to use</param>
/// <returns>the root of the generated tree</returns>
public static CssBox GenerateCssTree(string html, HtmlContainer htmlContainer, ref CssData cssData)
{
var root = HtmlParser.ParseDocument(html);
if (root != null)
{
bool cssDataChanged = false;
CascadeStyles(root, htmlContainer, ref cssData, ref cssDataChanged);
CorrectTextBoxes(root);
CorrectLineBreaksBlocks(root);
CorrectInlineBoxesParent(root);
CorrectBlockInsideInline(root);
CorrectInlineBoxesParent(root);
}
return(root);
}
