/// <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(IResourceServer resourceServer, Size minSize, Size maxSize, TextRenderingHint textRenderingHint = TextRenderingHint.AntiAlias, CssData cssData = null
)
{
if (string.IsNullOrEmpty(resourceServer.Html))
{
return(new Bitmap(0, 0, PixelFormat.Format32bppArgb));
}
using (var container = new HtmlContainer())
{
container.UseGdiPlusTextRendering = true;
container.SetResourceServer(resourceServer);
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>
/// On tooltip appear set the html by the associated control, layout and set the tooltip size by the html size.
/// </summary>
protected virtual void OnToolTipPopup(PopupEventArgs e)
{
//Create fragment container
var cssClass = string.IsNullOrEmpty(_tooltipCssClass) ? null : string.Format(" class=\"{0}\"", _tooltipCssClass);
ResourceServer.Html = string.Format("<div{0}>{1}</div>", cssClass, GetToolTip(e.AssociatedControl));
_htmlContainer.SetResourceServer(ResourceServer);
_htmlContainer.MaxSize = MaximumSize;
//Measure size of the container
using (var g = e.AssociatedControl.CreateGraphics())
{
g.TextRenderingHint = _textRenderingHint;
_htmlContainer.PerformLayout(g);
}
//Set the size of the tooltip
var desiredWidth = (int)Math.Ceiling(MaximumSize.Width > 0 ? Math.Min(_htmlContainer.ActualSize.Width, MaximumSize.Width) : _htmlContainer.ActualSize.Width);
var desiredHeight = (int)Math.Ceiling(MaximumSize.Height > 0 ? Math.Min(_htmlContainer.ActualSize.Height, MaximumSize.Height) : _htmlContainer.ActualSize.Height);
e.ToolTipSize = new Size(desiredWidth, desiredHeight);
#if !MONO
// start mouse handle timer
if (_allowLinksHandling)
{
_associatedControl = e.AssociatedControl;
_linkHandlingTimer.Start();
}
#endif
}
private void ResourceServer_Updated(object sender, ResourceServerUpdatedEventArgs e)
{
if (InvokeRequired)
{
Action callback = () => ResourceServer_Updated(sender, e);
Invoke(callback);
return;
}
_htmlContainer.SetResourceServer(ResourceServer);
PerformLayout();
Invalidate();
}
/// <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(IResourceServer resourceServer,
Size minSize, Size maxSize, Color backgroundColor = new Color(), CssData cssData = null
)
{
if (backgroundColor == Color.Transparent)
{
throw new ArgumentOutOfRangeException("backgroundColor", "Transparent background in not supported");
}
if (string.IsNullOrEmpty(resourceServer.Html))
{
return(new Bitmap(0, 0, PixelFormat.Format32bppArgb));
}
using (var container = new HtmlContainer())
{
container.SetResourceServer(resourceServer);
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>
/// Measure the size (width and height) required to draw the given html under given width and height restrictions.<br/>
/// </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="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 size required for the html</returns>
private static SizeF Measure(Graphics g, IResourceServer resourceServer,
float maxWidth, bool useGdiPlusTextRendering
)
{
SizeF actualSize = SizeF.Empty;
if (!string.IsNullOrEmpty(resourceServer.Html))
{
using (var container = new HtmlContainer())
{
container.MaxSize = new SizeF(maxWidth, 0);
container.UseGdiPlusTextRendering = useGdiPlusTextRendering;
container.SetResourceServer(resourceServer);
container.PerformLayout(g);
actualSize = container.ActualSize;
}
}
return(actualSize);
}
/// <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, IResourceServer resourceServer, PointF location, SizeF maxSize, bool useGdiPlusTextRendering
)
{
SizeF actualSize = SizeF.Empty;
if (!string.IsNullOrEmpty(resourceServer.Html))
{
using (var container = new HtmlContainer())
{
container.Location = location;
container.MaxSize = maxSize;
container.UseGdiPlusTextRendering = useGdiPlusTextRendering;
container.SetResourceServer(resourceServer);
container.PerformLayout(g);
container.PerformPaint(g);
actualSize = container.ActualSize;
}
}
return(actualSize);
}