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

   1 //
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   3 // a copy of this software and associated documentation files (the
   4 // "Software"), to deal in the Software without restriction, including
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   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 #if NET_2_0
  41         [SupportsEventValidation]
  42 #endif
  43         public class HtmlInputHidden : HtmlInputControl, IPostBackDataHandler {
  44
  45                 private static readonly object ServerChangeEvent = new object ();
  46
  47                 public HtmlInputHidden () : base ("hidden")
  48                 {
  49                 }
  50
  51                 bool LoadPostDataInternal (string postDataKey, NameValueCollection postCollection)
  52                 {
  53                         string data = postCollection [postDataKey];
  54                         if (data != null && data != Value) {
  55                                 Value = data;
  56                                 return true;
  57                         }
  58                         return false;
  59                 }
  60
  61                 void RaisePostDataChangedEventInternal ()
  62                 {
  63                         OnServerChange (EventArgs.Empty);
  64                 }
  65
  66 #if NET_2_0
  67                 protected virtual bool LoadPostData (string postDataKey, NameValueCollection postCollection)
  68                 {
  69                         return LoadPostDataInternal (postDataKey, postCollection);
  70                 }
  71
  72                 protected virtual void RaisePostDataChangedEvent ()
  73                 {
  74                         RaisePostDataChangedEventInternal ();
  75                 }
  76 #endif
  77
  78                 bool IPostBackDataHandler.LoadPostData (string postDataKey,
  79                                                         NameValueCollection postCollection)
  80                 {
  81 #if NET_2_0
  82                         return LoadPostData (postDataKey, postCollection);
  83 #else
  84                         return LoadPostDataInternal (postDataKey, postCollection);
  85 #endif
  86                 }
  87
  88                 void IPostBackDataHandler.RaisePostDataChangedEvent ()
  89                 {
  90 #if NET_2_0
  91                         RaisePostDataChangedEvent ();
  92 #else
  93                         RaisePostDataChangedEventInternal ();
  94 #endif
  95                 }
  96
  97 #if NET_2_0
  98                 protected internal
  99 #else
 100                 protected
 101 #endif
 102                 override void OnPreRender (EventArgs e)
 103                 {
 104                         base.OnPreRender (e);
 105
 106                         if (Page != null) {
 107                                 Page.RegisterRequiresPostBack (this);
 108                         }
 109                 }
 110
 111                 protected virtual void OnServerChange (EventArgs e)
 112                 {
 113                         EventHandler handler = (EventHandler) Events [ServerChangeEvent];
 114                         if (handler != null)
 115                                 handler (this, e);
 116                 }
 117
 118                 [WebSysDescription("")]
 119                 [WebCategory("Action")]
 120                 public event EventHandler ServerChange {
 121                         add { Events.AddHandler (ServerChangeEvent, value); }
 122                         remove { Events.RemoveHandler (ServerChangeEvent, value); }
 123                 }
 124         }
 125 }