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

   1 //
   2 // System.Web.UI.WebControls.LinkButton.cs
   3 //
   4 // Authors:
   5 //   Gaurav Vaish (gvaish@iitk.ac.in)
   6 //   Andreas Nahr (ClassDevelopment@A-SoftTech.com)
   7 //
   8 // (C) Gaurav Vaish (2002)
   9 // (C) 2003 Andreas Nahr
  10 //\r
  11
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32 \r
  33 using System;\r
  34 using System.Web;\r
  35 using System.Web.UI;\r
  36 using System.ComponentModel;
  37 using System.ComponentModel.Design;\r
  38 \r
  39 namespace System.Web.UI.WebControls\r
  40 {\r
  41         [DefaultEvent("Click")]\r
  42         [DefaultProperty("Text")]\r
  43         [ControlBuilder(typeof(LinkButtonControlBuilder))]\r
  44         [Designer("System.Web.UI.Design.WebControls.LinkButtonDesigner, " + Consts.AssemblySystem_Design, typeof (IDesigner))]\r
  45         [DataBindingHandler("System.Web.UI.Design.TextDataBindingHandler, " + Consts.AssemblySystem_Design)]\r
  46         [ParseChildren(false)]\r
  47         [ToolboxData("<{0}:LinkButton runat=\"server\">LinkButton</{0}:LinkButton>")]\r
  48         public class LinkButton : WebControl, IPostBackEventHandler\r
  49         {\r
  50                 private static readonly object ClickEvent   = new object();\r
  51                 private static readonly object CommandEvent = new object();\r
  52 \r
  53                 public LinkButton () : base (HtmlTextWriterTag.A)\r
  54                 {\r
  55                 }\r
  56
  57 #if NET_2_0\r
  58                 [ThemeableAttribute (false)]\r
  59 #else\r
  60                 [Bindable (false)]\r
  61 #endif\r
  62                 [DefaultValue (true), WebCategory ("Behavior")]
  63                 [WebSysDescription ("Determines if validation is performed when clicked.")]\r
  64                 public bool CausesValidation\r
  65                 {\r
  66                         get {\r
  67                                 object o = ViewState ["CausesValidation"];\r
  68                                 return (o == null) ? true : (bool) o;\r
  69                         }\r
  70 \r
  71                         set { ViewState ["CausesValidation"] = value; }\r
  72                 }\r
  73
  74 #if NET_2_0\r
  75                 [ThemeableAttribute (false)]\r
  76 #endif\r
  77                 [DefaultValue (""), Bindable (true), WebCategory ("Behavior")]
  78                 [WebSysDescription ("An argument for the Command of this control.")]\r
  79                 public string CommandArgument\r
  80                 {\r
  81                         get {\r
  82                                 object o = ViewState ["CommandArgument"];\r
  83                                 return (o == null) ? String.Empty : (string) o;\r
  84                         }\r
  85 \r
  86                         set { ViewState ["CommandArgument"] = value; }\r
  87                 }\r
  88
  89 #if NET_2_0\r
  90                 [ThemeableAttribute (false)]\r
  91 #endif\r
  92                 [DefaultValue (""), WebCategory ("Behavior")]
  93                 [WebSysDescription ("The name of the Command of this control.")]\r
  94                 public string CommandName\r
  95                 {\r
  96                         get {\r
  97                                 object o = ViewState ["CommandName"];\r
  98                                 return (o == null) ? String.Empty : (string) o;\r
  99                         }\r
 100 \r
 101                         set { ViewState ["CommandName"] = value; }\r
 102                 }\r
 103
 104 #if NET_2_0\r
 105                 [Localizable (true)]\r
 106 #endif\r
 107                 [DefaultValue (""), Bindable (true), WebCategory ("Appearance")]
 108                 [PersistenceMode (PersistenceMode.InnerDefaultProperty)]
 109                 [WebSysDescription ("The text that should be shown on this LinkButton.")]\r
 110                 public virtual string Text\r
 111                 {\r
 112                         get {\r
 113                                 object o = ViewState ["Text"];\r
 114                                 return (o == null) ? String.Empty : (string) o;\r
 115                         }\r
 116 \r
 117                         set { ViewState ["Text"] = value; }\r
 118                 }\r
 119
 120                 [WebCategory ("Action")]
 121                 [WebSysDescription ("Raised when the LinkButton is clicked.")]\r
 122                 public event EventHandler Click\r
 123                 {\r
 124                         add { Events.AddHandler(ClickEvent, value); }\r
 125                         remove { Events.RemoveHandler(ClickEvent, value); }\r
 126                 }\r
 127
 128                 [WebCategory ("Action")]
 129                 [WebSysDescription ("Raised when a LinkButton Command is executed.")]\r
 130                 public event CommandEventHandler Command\r
 131                 {\r
 132                         add { Events.AddHandler(CommandEvent, value); }\r
 133                         remove { Events.RemoveHandler(CommandEvent, value); }\r
 134                 }\r
 135 \r
 136                 protected virtual void OnClick (EventArgs e)\r
 137                 {\r
 138                         if(Events != null){\r
 139                                 EventHandler eh = (EventHandler) (Events [ClickEvent]);\r
 140                                 if (eh != null)\r
 141                                         eh (this, e);\r
 142                         }\r
 143                 }\r
 144 \r
 145                 protected virtual void OnCommand (CommandEventArgs e)\r
 146                 {\r
 147                         if(Events != null){\r
 148                                 CommandEventHandler ceh = (CommandEventHandler) (Events [CommandEvent]);\r
 149                                 if (ceh != null)\r
 150                                         ceh (this, e);\r
 151                         }\r
 152                         RaiseBubbleEvent (this, e);\r
 153                 }\r
 154 \r
 155                 protected override void OnPreRender (EventArgs e)\r
 156                 {\r
 157                         base.OnPreRender(e);\r
 158                 }\r
 159 \r
 160                 void IPostBackEventHandler.RaisePostBackEvent (string eventArgument)\r
 161                 {\r
 162                         if (CausesValidation)\r
 163                                 Page.Validate ();\r
 164                         OnClick (EventArgs.Empty);\r
 165                         OnCommand (new CommandEventArgs (CommandName, CommandArgument));\r
 166                 }\r
 167 \r
 168                 protected override void AddAttributesToRender (HtmlTextWriter writer)\r
 169                 {\r
 170                         base.AddAttributesToRender (writer);\r
 171                         if (Enabled && Page != null){\r
 172                                 if (CausesValidation && Page.Validators.Count > 0){\r
 173                                         writer.AddAttribute (HtmlTextWriterAttribute.Href,\r
 174                                                              "javascript:" + \r
 175                                                              Utils.GetClientValidatedPostBack (this));\r
 176                                         return;\r
 177                                 }\r
 178                                 writer.AddAttribute (HtmlTextWriterAttribute.Href,\r
 179                                                      Page.GetPostBackClientHyperlink (this, ""));\r
 180                         }\r
 181                 }\r
 182 \r
 183                 protected override void AddParsedSubObject (object obj)\r
 184                 {\r
 185                         if (HasControls ()){\r
 186                                 base.AddParsedSubObject (obj);\r
 187                                 return;\r
 188                         }\r
 189 \r
 190                         if (obj is LiteralControl){\r
 191                                 Text = ((LiteralControl) obj).Text;\r
 192                                 return;\r
 193                         }\r
 194 \r
 195                         if (Text.Length > 0){\r
 196                                 base.AddParsedSubObject (new LiteralControl (Text));\r
 197                                 Text = String.Empty;\r
 198                         }\r
 199 \r
 200                         base.AddParsedSubObject (obj);\r
 201                 }\r
 202 \r
 203                 protected override void LoadViewState (object savedState)\r
 204                 {\r
 205                         if (savedState != null){\r
 206                                 base.LoadViewState (savedState);\r
 207                                 string savedText = (string) ViewState ["Text"];\r
 208                                 if (savedText != null)\r
 209                                         Text = savedText;\r
 210                         }\r
 211                 }\r
 212 \r
 213                 protected override void RenderContents (HtmlTextWriter writer)\r
 214                 {\r
 215                         if (HasControls ()){\r
 216                                 base.RenderContents (writer);\r
 217                                 return;\r
 218                         }\r
 219                         writer.Write (Text);\r
 220                 }\r
 221         }\r
 222 }\r