/// <summary>
/// Calls the ContentPlaceHolderHeadRepair.Repair method
/// </summary>
/// <param name="e"></param>
protected override void OnLoad(EventArgs e)
{
//Parses link, meta, and script tags that got missed by the Head>CPH bug.
ContentPlaceHolderFixes.RepairPageHeader(this);
//Fire the events later
base.OnLoad(e);
}
/// <summary>
/// Reparses meta and link tags that weren't parsed correctly the first time.
/// Only works inside ContentPlaceHolder controls located inside the head.
/// 1) Parses literal controls: looks for self-closing and empty meta, link, and script controls.
/// Supports Visible and EnableViewState attributes correctly. EnableViewState=false if not specified.
/// The TemplateControl is re-calculated.
/// 2) Parses HtmlGenericControls (link, meta, script tags with runat="server"). HtmlGenericControl instances for 'script' can
/// only exist if added through code, since <script runat="server"> is for server side code. Supports it anyway :)
/// Supports Visible and EnableViewState attributes correctly. EnableViewState=false if not specified.
/// The TemplateControl is re-calculated.
/// Note: script references don't have a built-in control, so we use a custom ScriptReference instance to provide the rebasing support.
/// </summary>
/// <param name="p"></param>
public static void RepairPageHeader(Page p)
{
//Aquire a collection of references to each contentplaceholder in the Head section.
//ContentPlaceHolders do not account for being located in an HtmlHead, and simply
//perform the normal parsing logic. We will patch this by iterating through incorrectly identified tags such as
//<link> and <meta>, and replacing them with the proper control type.
//As a bonus, we also make script references work, but that is an extra - Head doesn't usually do anything special
//with those anyway.
//Note that each contentplaceholder usually contains a child ContentPlaceHolder
if (p.Header != null)
{
////////////////////// Literal parsing //////////////////////////////
//Get a collection of all of the LiteralControls in the head
//This will handle link, meta, and script includes
List <LiteralControl> toParse = ControlUtils.GetControlsOfType <LiteralControl>(p.Header);
//handle literal links
if (toParse != null)
{
foreach (LiteralControl lc in toParse)
{
//if the literal is directly inside a content tag, on a content page, the TemplateControl property will
//incorrectly point to the MasterPage.
//So if we use lc.AppRelativeTemplateSourceDirectory, it doesn't work
//However, if we use this.AppRelativeTemplateSourceDirectory and
//we have a MasterPage>MasterPage(with relative literal stylesheet reference)>Page
//Then the relative stylesheet reference will be broke, relative to the Page.
//The solution is to find the child TemplateControl of lc's nearest ContentPlaceHolder parent.
//We do this before ParseLiteral control, because this value will be propogated to the
//component controls.
lc.TemplateControl = ContentPlaceHolderFixes.GetAdjustedParentTemplateControl(lc);
//Parse literal control
Control c = ParseLiteralControl(lc, lc.Text);
//notused: //Article.SetPathRecursive(c, getAdjustedParent(lc).AppRelativeTemplateSourceDirectory);//used to be this.
//Replace
lc.Parent.Controls.AddAt(lc.Parent.Controls.IndexOf(lc), c);
lc.Parent.Controls.Remove(lc);
}
}
//handle links with runat="server"
//We just want the outermost cphs
List <ContentPlaceHolder> cphList = ControlUtils.GetControlsOfType <ContentPlaceHolder>(p.Header, false, true);
if (cphList != null)
{
//There may be multiple CPHs in the head section
foreach (ContentPlaceHolder cph in cphList)
{
//Get a collection of all of the HtmlGenericControls in the current ContentPlaceHolder.
List <HtmlGenericControl> toFix = ControlUtils.GetControlsOfType <HtmlGenericControl>(cph);
if (toFix == null)
{
continue;
}
//This will handle all link tags, meta tags, or script tags with runat="server"
//Also affects script tags parsed in above section (URL resolution)
//Iterate through the collection, replacing or modifying the neccesary objects.
foreach (HtmlGenericControl hgc in toFix)
{
HtmlControl replacement = null;
switch (hgc.TagName.ToLower())
{
case "link":
//Create a replacement HtmlLink object with identical attributes.
//HtmlLink will resolve virtual URLs on the href attribute at render-time, unlike HtmlGenericControl.
replacement = new HtmlLink();
break;
case "meta":
//Create a replacement HtmlMeta object with identical attributes.
replacement = new HtmlMeta();
break;
case "script":
//Create a new script reference, which resolves the src attribute at render-time
replacement = new ScriptReference();
break;
}
if (replacement != null)
{
//Adjust the TemplateControl for the *other* ContentPlaceHolder bug.
replacement.TemplateControl = GetAdjustedParentTemplateControl(hgc.TemplateControl);
//Turn off ViewState
replacement.EnableViewState = false;
//Copy attributes
foreach (string s in hgc.Attributes.Keys)
{
string val = hgc.Attributes[s];
replacement.Attributes.Add(s, val);
}
//Assign known properties that aren.t collection-backed
replacement.EnableViewState = hgc.EnableViewState;
replacement.Visible = hgc.Visible;
//Insert the new object next to the old, then remove the old.
hgc.Parent.Controls.AddAt(hgc.Parent.Controls.IndexOf(hgc), replacement);
hgc.Parent.Controls.Remove(hgc);
}
}
}
}
}
/* Analyize TemplateControls. Prints TemplateControl/TemplateSourceDirectory tree for diagnostics.
* List<Control> allcontrols = GetControlsOfType<Control>(this);
* List<TemplateControl> uniqueTemplateControls =new List<TemplateControl>();
* Debug.WriteLine(Page.AppRelativeTemplateSourceDirectory);
* foreach (Control c in allcontrols)
* {
* //Debug.WriteLine(c.ID + " (" + c.TemplateControl.ID + ") - " + c.AppRelativeTemplateSourceDirectory);
* if (!uniqueTemplateControls.Contains(c.TemplateControl)){
* uniqueTemplateControls.Add(c.TemplateControl);
* string s = c.TemplateSourceDirectory;
* }
*
* }
* StringWriter sw = new StringWriter();
* PrintTree(this.Header, 0, sw);
* this.Header.Controls.AddAt(0, new LiteralControl(Server.HtmlEncode((sw.ToString()))));
*/
}