mcs/class/System.Web/System.Web.UI.WebControls/ListItem.cs

   1 //
   2 // System.Web.UI.WebControls.ListItem.cs
   3 //
   4 // Authors:
   5 //      Ben Maurer (bmaurer@novell.com)
   6 //
   7 // (C) 2005-2009 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 using System.Collections.Specialized;
  30 using System.ComponentModel;
  31 using System.Security.Permissions;
  32
  33 namespace System.Web.UI.WebControls {
  34
  35         // CAS - no inheritance demand required because the class is sealed
  36         [AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  37         // attributes
  38         [ControlBuilder(typeof(ListItemControlBuilder))]
  39         [TypeConverter(typeof(System.ComponentModel.ExpandableObjectConverter))]
  40         [ParseChildren (true, "Text")]
  41         public sealed class ListItem : IAttributeAccessor, IParserAccessor, IStateManager
  42         {
  43                 public ListItem (string text, string value, bool enabled) : this (text, value)
  44                 {
  45                         this.enabled = enabled;
  46                 }
  47                 public ListItem (string text, string value)
  48                 {
  49                         this.text = text;
  50                         this.value = value;
  51                 }
  52
  53                 public ListItem (string text) : this (text, null)
  54                 {
  55                 }
  56
  57                 public ListItem () : this (null, null)
  58                 {
  59                 }
  60
  61                 public static ListItem FromString (string text)
  62                 {
  63                         return new ListItem (text);
  64                 }
  65
  66                 public override bool Equals (object o)
  67                 {
  68                         ListItem li = o as ListItem;
  69                         if (li == null)
  70                                 return false;
  71                         return li.Text == Text && li.Value == Value;
  72                 }
  73
  74                 public override int GetHashCode ()
  75                 {
  76                         return Text.GetHashCode () ^ Value.GetHashCode ();
  77
  78                 }
  79
  80                 string IAttributeAccessor.GetAttribute (string key)
  81                 {
  82                         if (attrs == null)
  83                                 return null;
  84
  85                         return (string) Attributes [key];
  86                 }
  87
  88                 void IAttributeAccessor.SetAttribute (string key, string value)
  89                 {
  90                         Attributes [key] = value;
  91                 }
  92
  93                 void IParserAccessor.AddParsedSubObject (object obj)
  94                 {
  95                         LiteralControl lc = obj as LiteralControl;
  96                         if (lc == null) {
  97                                 // obj.GetType() will throw a NullRef if obj is null. That's fine according to the test.
  98                                 throw new HttpException ("'ListItem' cannot have children of type " + obj.GetType ());
  99                         }
 100                         Text = lc.Text;
 101                 }
 102
 103                 void IStateManager.LoadViewState (object state)
 104                 {
 105                         LoadViewState (state);
 106                 }
 107
 108                 internal void LoadViewState (object state)
 109                 {
 110                         if (state == null)
 111                                 return;
 112
 113                         object [] states = (object []) state;
 114
 115                         if (states [0] != null) {
 116                                 sb = new StateBag (true);
 117                                 sb.LoadViewState (states[0]);
 118                                 sb.SetDirty (true);
 119                         }
 120
 121                         if (states [1] != null)
 122                                 text = (string) states [1];
 123                         if (states [2] != null)
 124                                 value = (string) states [2];
 125                         if (states [3] != null)
 126                                 selected = (bool) states [3];
 127                         if (states [4] != null)
 128                                 enabled = (bool) states [4];
 129                 }
 130
 131                 object IStateManager.SaveViewState ()
 132                 {
 133                         return SaveViewState ();
 134                 }
 135
 136                 internal object SaveViewState ()
 137                 {
 138                         if (!dirty)
 139                                 return null;
 140
 141                         object [] state = new object [5];
 142                         state [0] = sb != null ? sb.SaveViewState () : null;
 143                         state [1] = (object) text;
 144                         state [2] = (object) value;
 145                         state [3] = (object) selected;
 146                         state [4] = (object) enabled;
 147                         return state;
 148                 }
 149
 150                 void IStateManager.TrackViewState ()
 151                 {
 152                         TrackViewState ();
 153                 }
 154
 155                 internal void TrackViewState ()
 156                 {
 157                         tracking = true;
 158                         if (sb != null) {
 159                                 sb.TrackViewState ();
 160                                 sb.SetDirty (true);
 161                         }
 162                 }
 163
 164                 public override string ToString ()
 165                 {
 166                         return Text;
 167                 }
 168
 169                 [Browsable(false)]
 170                 [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
 171                 public AttributeCollection Attributes {
 172                         get {
 173                                 if (attrs != null)
 174                                         return attrs;
 175
 176                                 if (sb == null) {
 177                                         sb = new StateBag (true);
 178                                         if (tracking)
 179                                                 sb.TrackViewState ();
 180                                 }
 181
 182                                 return attrs = new AttributeCollection (sb);
 183                         }
 184                 }
 185
 186                 bool IStateManager.IsTrackingViewState {
 187                         get { return tracking; }
 188                 }
 189
 190                 [TypeConverter ("System.Web.UI.MinimizableAttributeTypeConverter")]
 191                 [DefaultValue(false)]
 192                 public bool Selected {
 193                         get { return selected; }
 194                         set {
 195                                 selected = value;
 196                                 if (tracking)
 197                                         SetDirty ();
 198                         }
 199                 }
 200
 201                 [Localizable (true)]
 202                 [DefaultValue("")]
 203                 [PersistenceMode(PersistenceMode.EncodedInnerDefaultProperty)]
 204                 public string Text {
 205                         get {
 206                                 string r = text;
 207                                 if (r == null)
 208                                         r = value;
 209                                 if (r == null)
 210                                         r = String.Empty;
 211                                 return r;
 212                         }
 213
 214                         set {
 215                                 text = value;
 216                                 if (tracking)
 217                                         SetDirty ();
 218                         }
 219                 }
 220
 221                 [Localizable (true)]
 222                 [DefaultValue("")]
 223                 public string Value {
 224                         get {
 225                                 string r = value;
 226                                 if (r == null)
 227                                         r = text;
 228                                 if (r == null)
 229                                         r = String.Empty;
 230                                 return r;
 231                         }
 232
 233                         set {
 234                                 this.value = value;
 235                                 if (tracking)
 236                                         SetDirty ();
 237                         }
 238                 }
 239
 240                 internal void SetDirty ()
 241                 {
 242                         dirty = true;
 243                 }
 244
 245                 [DefaultValue (true)]
 246                 public bool Enabled
 247                 {
 248                         get { return enabled; }
 249                         set {
 250                                 enabled = value;
 251                                 if (tracking)
 252                                         SetDirty ();
 253                         }
 254                 }
 255
 256                 internal bool HasAttributes {
 257                         get { return attrs != null && attrs.Count > 0; }
 258                 }
 259
 260                 string text;
 261                 string value;
 262                 bool selected;
 263                 bool dirty;
 264                 bool enabled = true;
 265                 bool tracking;
 266                 StateBag sb;
 267                 AttributeCollection attrs;
 268         }
 269 }