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

   1 //
   2 // Permission is hereby granted, free of charge, to any person obtaining
   3 // a copy of this software and associated documentation files (the
   4 // "Software"), to deal in the Software without restriction, including
   5 // without limitation the rights to use, copy, modify, merge, publish,
   6 // distribute, sublicense, and/or sell copies of the Software, and to
   7 // permit persons to whom the Software is furnished to do so, subject to
   8 // the following conditions:
   9 //
  10 // The above copyright notice and this permission notice shall be
  11 // included in all copies or substantial portions of the Software.
  12 //
  13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  14 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  15 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  16 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  17 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  18 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  19 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  20 //
  21 //
  22 // System.Web.UI.HtmlControls.HtmlInputHidden.cs
  23 //
  24 // Authors:
  25 //      Jackson Harper (jackson@ximian.com)
  26 //
  27 // (C) 2005 Novell, Inc.
  28
  29 using System.ComponentModel;
  30 using System.Collections.Specialized;
  31 using System.Security.Permissions;
  32
  33 namespace System.Web.UI.HtmlControls {
  34
  35         // CAS
  36         [AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  37         [AspNetHostingPermission (SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  38         // attributes
  39         [DefaultEvent ("ServerChange")]
  40         public class HtmlInputHidden : HtmlInputControl, IPostBackDataHandler {
  41
  42                 private static readonly object ServerChangeEvent = new object ();
  43
  44                 public HtmlInputHidden () : base ("hidden")
  45                 {
  46                 }
  47
  48                 bool LoadPostDataInternal (string postDataKey, NameValueCollection postCollection)
  49                 {
  50                         string data = postCollection [postDataKey];
  51                         if (data != null && data != Value) {
  52                                 Value = data;
  53                                 return true;
  54                         }
  55                         return false;
  56                 }
  57
  58                 void RaisePostDataChangedEventInternal ()
  59                 {
  60                         OnServerChange (EventArgs.Empty);
  61                 }
  62
  63 #if NET_2_0
  64                 protected virtual bool LoadPostData (string postDataKey, NameValueCollection postCollection)
  65                 {
  66                         return LoadPostDataInternal (postDataKey, postCollection);
  67                 }
  68
  69                 protected virtual void RaisePostDataChangedEvent ()
  70                 {
  71                         RaisePostDataChangedEventInternal ();
  72                 }
  73 #endif
  74
  75                 bool IPostBackDataHandler.LoadPostData (string postDataKey,
  76                                                         NameValueCollection postCollection)
  77                 {
  78 #if NET_2_0
  79                         return LoadPostData (postDataKey, postCollection);
  80 #else
  81                         return LoadPostDataInternal (postDataKey, postCollection);
  82 #endif
  83                 }
  84
  85                 void IPostBackDataHandler.RaisePostDataChangedEvent ()
  86                 {
  87 #if NET_2_0
  88                         RaisePostDataChangedEvent ();
  89 #else
  90                         RaisePostDataChangedEventInternal ();
  91 #endif
  92                 }
  93
  94 #if NET_2_0
  95                 protected internal
  96 #else
  97                 protected
  98 #endif
  99                 override void OnPreRender (EventArgs e)
 100                 {
 101                         base.OnPreRender (e);
 102
 103                         if (Page != null) {
 104                                 Page.RegisterRequiresPostBack (this);
 105                         }
 106                 }
 107
 108                 protected virtual void OnServerChange (EventArgs e)
 109                 {
 110                         EventHandler handler = (EventHandler) Events [ServerChangeEvent];
 111                         if (handler != null)
 112                                 handler (this, e);
 113                 }
 114
 115                 [WebSysDescription("")]
 116                 [WebCategory("Action")]
 117                 public event EventHandler ServerChange {
 118                         add { Events.AddHandler (ServerChangeEvent, value); }
 119                         remove { Events.RemoveHandler (ServerChangeEvent, value); }
 120                 }
 121         }
 122 }