mcs/class/System.Web/System.Web.UI.HtmlControls/HtmlHead.cs

   1 //
   2 // System.Web.UI.HtmlControls.HtmlHead
   3 //
   4 // Authors:
   5 //      Lluis Sanchez Gual (lluis@novell.com)
   6 //
   7 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 #if NET_2_0
  30
  31 using System.ComponentModel;
  32 using System.Collections;
  33 using System.Security.Permissions;
  34 using System.Web.UI.WebControls;
  35
  36 namespace System.Web.UI.HtmlControls
  37 {
  38         // CAS - no InheritanceDemand here as the class is sealed
  39         [AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  40         // attributes
  41         [ControlBuilder (typeof(HtmlHeadBuilder))]
  42         public sealed class HtmlHead: HtmlGenericControl, IPageHeader, IParserAccessor
  43         {
  44                 HtmlTitle title;
  45                 Hashtable metadata;
  46                 ArrayList styleSheets;
  47                 StyleSheetBag styleSheet;
  48
  49                 public HtmlHead(): base("head") {}
  50
  51                 public HtmlHead (string tag) : base (tag)
  52                 {
  53                 }
  54
  55                 protected internal override void OnInit (EventArgs e)
  56                 {
  57                         Page.SetHeader (this);
  58                 }
  59
  60                 protected internal override void RenderChildren (HtmlTextWriter writer)
  61                 {
  62                         base.RenderChildren (writer);
  63                         if (metadata != null) {
  64                                 foreach (DictionaryEntry entry in metadata) {
  65                                         writer.AddAttribute ("name", entry.Key.ToString ());
  66                                         writer.AddAttribute ("content", entry.Value.ToString ());
  67                                         writer.RenderBeginTag (HtmlTextWriterTag.Meta);
  68                                         writer.RenderEndTag ();
  69                                 }
  70                         }
  71
  72                         if (styleSheet != null)
  73                                 styleSheet.Render (writer);
  74                 }
  75
  76                 protected internal override void AddedControl (Control control, int index)
  77                 {
  78                         if (control is HtmlTitle)
  79                                 title = (HtmlTitle) control;
  80
  81                         base.AddedControl (control, index);
  82                 }
  83
  84                 protected internal override void RemovedControl (Control control)
  85                 {
  86                         if (title == control)
  87                                 title = null;
  88
  89                         base.RemovedControl (control);
  90                 }
  91
  92                 IList IPageHeader.LinkedStyleSheets {
  93                         get {
  94                                 if (styleSheets == null) styleSheets = new ArrayList ();
  95                                 return styleSheets;
  96                         }
  97                 }
  98
  99                 IDictionary IPageHeader.Metadata {
 100                         get {
 101                                 if (metadata == null) metadata = new Hashtable ();
 102                                 return metadata;
 103                         }
 104                 }
 105
 106                 IStyleSheet IPageHeader.StyleSheet {
 107                         get {
 108                                 if (styleSheet == null) styleSheet = new StyleSheetBag ();
 109                                 return styleSheet;
 110                         }
 111                 }
 112
 113                 string IPageHeader.Title {
 114                         get { return title.Text; }
 115                         set { title.Text = value; }
 116                 }
 117         }
 118
 119         internal class StyleSheetBag: IStyleSheet
 120         {
 121                 ArrayList entries = new ArrayList ();
 122
 123                 internal class StyleEntry
 124                 {
 125                         public Style Style;
 126                         public string Selection;
 127                         public IUrlResolutionService UrlResolver;
 128                 }
 129
 130                 public StyleSheetBag ()
 131                 {
 132                 }
 133
 134                 public void CreateStyleRule (Style style, string selection, IUrlResolutionService urlResolver)
 135                 {
 136                         StyleEntry entry = new StyleEntry ();
 137                         entry.Style = style;
 138                         entry.UrlResolver = urlResolver;
 139                         entry.Selection = selection;
 140                         entries.Add (entry);
 141                 }
 142
 143                 public void RegisterStyle (Style style, IUrlResolutionService urlResolver)
 144                 {
 145                         for (int n=0; n<entries.Count; n++) {
 146                                 if (((StyleEntry)entries[n]).Style == style)
 147                                         return;
 148                         }
 149
 150                         string name = "aspnet_" + entries.Count;
 151                         style.SetRegisteredCssClass (name);
 152                         CreateStyleRule (style, "." + name, urlResolver);
 153                 }
 154
 155                 public void Render (HtmlTextWriter writer)
 156                 {
 157                         writer.AddAttribute ("type", "text/css");
 158                         writer.RenderBeginTag (HtmlTextWriterTag.Style);
 159
 160                         foreach (StyleEntry entry in entries) {
 161                                 CssStyleCollection sts = entry.Style.GetStyleAttributes (entry.UrlResolver);
 162                                 writer.Write ("\n" + entry.Selection + " {" + sts.BagToString () + "}");
 163                         }
 164
 165                         writer.RenderEndTag ();
 166                 }
 167         }
 168 }
 169
 170 #endif