mcs/class/System.Web/System.Web.UI/CssStyleCollection.cs

   1 //
   2 // System.Web.UI.CssStyleCollection.cs
   3 //
   4 // Authors:
   5 //      Duncan Mak  (duncan@ximian.com)
   6 //      Gonzalo Paniagua (gonzalo@ximian.com)
   7 //
   8 // (C) 2002 Ximian, Inc. (http://www.ximian.com)
   9 // Copyright (C) 2005 Novell, Inc (http://www.novell.com)
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System.IO;
  32 using System.Collections;
  33 using System.Security.Permissions;
  34 using System.Text;
  35 using System.Collections.Specialized;
  36 using System.Globalization;
  37
  38 namespace System.Web.UI {
  39
  40         // CAS - no InheritanceDemand here as the class is sealed
  41         [AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  42         public sealed class CssStyleCollection
  43         {
  44                 StateBag bag;
  45                 HybridDictionary style;
  46                 StringBuilder _value = new StringBuilder ();
  47
  48                 internal CssStyleCollection ()
  49                 {
  50 #if NET_2_0
  51                         style = new HybridDictionary (true);
  52 #else
  53                         style = new HybridDictionary (false);
  54 #endif
  55                 }
  56
  57                 internal CssStyleCollection (StateBag bag) : this ()
  58                 {
  59                         this.bag = bag;
  60                         if (bag != null && bag [AttributeCollection.StyleAttribute] != null)
  61                                 _value.Append (bag [AttributeCollection.StyleAttribute]);
  62                         InitFromStyle ();
  63                 }
  64
  65                 void InitFromStyle ()
  66                 {
  67                         style.Clear ();
  68                         if (_value.Length > 0) {
  69                                 int startIndex = 0;
  70                                 while (startIndex >= 0)
  71                                         startIndex = ParseStyle (startIndex);
  72                         }
  73                 }
  74
  75                 int ParseStyle (int startIndex)
  76                 {
  77                         int colon = -1;
  78                         for (int i = startIndex; i < _value.Length; i++) {
  79                                 if (_value [i] == ':') {
  80                                         colon = i;
  81                                         break;
  82                                 }
  83                         }
  84                         if (colon == -1 || colon + 1 == _value.Length)
  85                                 return -1;
  86
  87                         string key = _value.ToString (startIndex, colon - startIndex).Trim ();
  88
  89                         int semicolon = -1;
  90                         for (int i = colon + 1; i < _value.Length; i++) {
  91                                 if (_value [i] == ';') {
  92                                         semicolon = i;
  93                                         break;
  94                                 }
  95                         }
  96                         string value;
  97                         if (semicolon == -1)
  98                                 value = _value.ToString (colon + 1, _value.Length - colon - 1).Trim ();
  99                         else
 100                                 value = _value.ToString (colon + 1, semicolon - colon - 1).Trim ();
 101
 102                         style.Add (key, value);
 103                         if (semicolon == -1 || semicolon + 1 == _value.Length)
 104                                 return -1;
 105
 106                         return semicolon + 1;
 107                 }
 108
 109                 void BagToValue ()
 110                 {
 111                         _value.Length = 0;
 112                         foreach (string key in style.Keys)
 113                                 AppendStyle (_value, key, (string) style [key]);
 114                 }
 115
 116                 static void AppendStyle (StringBuilder sb, string key, string value)
 117                 {
 118 #if NET_2_0
 119                         if (String.Compare (key, "background-image", StringComparison.OrdinalIgnoreCase) == 0 &&
 120                             value.Length >= 3 && String.Compare ("url", 0, value, 0, 3, StringComparison.OrdinalIgnoreCase) != 0)
 121 #else
 122                         if (key == "background-image" && 0 != String.Compare ("url", value.Substring (0, 3), true,
 123                                                                               CultureInfo.InvariantCulture))
 124 #endif
 125                                 sb.AppendFormat ("{0}:url({1});", key, HttpUtility.UrlPathEncode (value));
 126                         else
 127                                 sb.AppendFormat ("{0}:{1};", key, value);
 128                 }
 129
 130                 public int Count {
 131                         get { return style.Count; }
 132                 }
 133
 134                 public string this [string key] {
 135                         get { return style [key] as string; }
 136                         set { Add (key, value); }
 137                 }
 138
 139                 public ICollection Keys {
 140                         get { return style.Keys; }
 141                 }
 142
 143                 public void Add (string key, string value)
 144                 {
 145                         if (key == null)
 146                                 throw new ArgumentNullException ("key");
 147
 148                         if (value == null) {
 149                                 Remove (key);
 150                                 return;
 151                         }
 152
 153                         string curr = (string) style [key];
 154                         if (curr == null) {
 155                                 // just append
 156                                 style [key] = value;
 157                                 AppendStyle (_value, key, value);
 158                         } else if (String.CompareOrdinal (curr, value) == 0) {
 159                                 // do nothing
 160                                 return;
 161                         } else {
 162                                 style [key] = value;
 163                                 BagToValue ();
 164                         }
 165
 166                         if (bag != null)
 167                                 bag [AttributeCollection.StyleAttribute] = _value.ToString ();
 168                 }
 169
 170 #if NET_2_0
 171                 public
 172 #else
 173                 internal
 174 #endif
 175                 void Add (HtmlTextWriterStyle key, string value)
 176                 {
 177                         Add (HtmlTextWriter.StaticGetStyleName (key), value);
 178                 }
 179
 180                 public void Clear ()
 181                 {
 182                         style.Clear ();
 183                         SetValueInternal (null);
 184                 }
 185
 186                 public void Remove (string key)
 187                 {
 188                         if (style [key] == null)
 189                                 return;
 190                         style.Remove (key);
 191                         if (style.Count == 0)
 192                                 SetValueInternal (null);
 193                         else
 194                                 BagToValue ();
 195                 }
 196 #if NET_2_0
 197                 public string this [HtmlTextWriterStyle key] {
 198                         get { return style [HtmlTextWriter.StaticGetStyleName (key)] as string; }
 199                         set { Add (HtmlTextWriter.StaticGetStyleName (key), value); }
 200                 }
 201
 202                 public void Remove (HtmlTextWriterStyle key)
 203                 {
 204                         Remove (HtmlTextWriter.StaticGetStyleName (key));
 205                 }
 206
 207                 public
 208 #else
 209                 internal
 210 #endif
 211                 string Value {
 212                         get { return _value.ToString (); }
 213                         set {
 214                                 SetValueInternal (value);
 215                                 InitFromStyle ();
 216                         }
 217                 }
 218
 219                 void SetValueInternal (string value)
 220                 {
 221                         _value.Length = 0;
 222                         if (value != null)
 223                                 _value.Append (value);
 224                         if (bag != null) {
 225                                 if (value == null)
 226                                         bag.Remove (AttributeCollection.StyleAttribute);
 227                                 else
 228                                         bag [AttributeCollection.StyleAttribute] = value;
 229                         }
 230                 }
 231         }
 232 }
 233