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

   1 /**\r
   2  * Namespace: System.Web.UI.WebControls\r
   3  * Class:     ImageButton\r
   4  *\r
   5  * Author:  Gaurav Vaish\r
   6  * Maintainer: gvaish@iitk.ac.in\r
   7  * Contact: <my_scripts2001@yahoo.com>, <gvaish@iitk.ac.in>\r
   8  * Implementation: yes\r
   9  * Status:  100%\r
  10  *\r
  11  * (C) Gaurav Vaish (2001)\r
  12  */\r
  13 \r
  14 using System;\r
  15 using System.Collections;\r
  16 using System.Collections.Specialized;\r
  17 using System.Web;\r
  18 using System.Web.UI;\r
  19 \r
  20 namespace System.Web.UI.WebControls\r
  21 {\r
  22         [DefaultEvent("Click")]\r
  23         public class ImageButton: Image, IPostBackDataHandler, IPostBackEventHandler\r
  24         {\r
  25                 private static readonly object ClickEvent   = new object();\r
  26                 private static readonly object CommandEvent = new object();\r
  27 \r
  28                 private int x, y;\r
  29 \r
  30                 public ImageButton(): base()\r
  31                 {\r
  32                 }\r
  33 \r
  34                 public bool CausesValidation\r
  35                 {\r
  36                         get\r
  37                         {\r
  38                                 object o = ViewState["CausesValidation"];\r
  39                                 if(o!=null)\r
  40                                         return (bool)o;\r
  41                                 return true;\r
  42                         }\r
  43                         set\r
  44                         {\r
  45                                 ViewState["CausesValidation"] = value;\r
  46                         }\r
  47                 }\r
  48 \r
  49                 public string CommandArgument\r
  50                 {\r
  51                         get\r
  52                         {\r
  53                                 object o = ViewState["CommandArgument"];\r
  54                                 if(o!=null)\r
  55                                         return (string)o;\r
  56                                 return String.Empty;\r
  57                         }\r
  58                         set\r
  59                         {\r
  60                                 ViewState["CommandArgument"] = value;\r
  61                         }\r
  62                 }\r
  63 \r
  64                 public string CommandName\r
  65                 {\r
  66                         get\r
  67                         {\r
  68                                 object o = ViewState["CommandName"];\r
  69                                 if(o!=null)\r
  70                                         return (string)o;\r
  71                                 return String.Empty;\r
  72                         }\r
  73                         set\r
  74                         {\r
  75                                 ViewState["CommandName"] = value;\r
  76                         }\r
  77                 }\r
  78 \r
  79                 protected override HtmlTextWriterTag TagKey\r
  80                 {\r
  81                         get\r
  82                         {\r
  83                                 return HtmlTextWriterTag.Input;\r
  84                         }\r
  85                 }\r
  86 \r
  87                 public event ImageClickEventHandler Click\r
  88                 {\r
  89                         add\r
  90                         {\r
  91                                 Events.AddHandler(ClickEvent, value);\r
  92                         }\r
  93                         remove\r
  94                         {\r
  95                                 Events.RemoveHandler(ClickEvent, value);\r
  96                         }\r
  97                 }\r
  98 \r
  99                 public event CommandEventHandler Command\r
 100                 {\r
 101                         add\r
 102                         {\r
 103                                 Events.AddHandler(CommandEvent, value);\r
 104                         }\r
 105                         remove\r
 106                         {\r
 107                                 Events.RemoveHandler(CommandEvent, value);\r
 108                         }\r
 109                 }\r
 110 \r
 111                 protected override void AddAttributesToRender(HtmlTextWriter writer)\r
 112                 {\r
 113                         writer.AddAttribute(HtmlTextWriterAttribute.Type, "image");\r
 114                         writer.AddAttribute(HtmlTextWriterAttribute.Name, UniqueID);\r
 115                         if(Page != null && CausesValidation)\r
 116                         {\r
 117                                 if(Page.Validators.Count > 0)\r
 118                                 {\r
 119                                         writer.AddAttribute(HtmlTextWriterAttribute.Onclick, Utils.GetClientValidatedEvent());\r
 120                                         writer.AddAttribute("language", "javascript");\r
 121                                 }\r
 122                         }\r
 123                         AddAttributesToRender(writer);\r
 124                 }\r
 125 \r
 126                 protected virtual void OnClick(ImageClickEventArgs e)\r
 127                 {\r
 128                         if(Events != null)\r
 129                         {\r
 130                                 ImageClickEventHandler iceh = (ImageClickEventHandler)(Events[ClickEvent]);\r
 131                                 if(iceh != null)\r
 132                                         iceh(this, e);\r
 133                         }\r
 134                 }\r
 135 \r
 136                 protected virtual void OnCommand(CommandEventArgs e)\r
 137                 {\r
 138                         if(Events != null)\r
 139                         {\r
 140                                 CommandEventHandler ceh = (CommandEventHandler)(Events[CommandEvent]);\r
 141                                 if(ceh != null)\r
 142                                         ceh(this, e);\r
 143                                 RaiseBubbleEvent(this, e);\r
 144                         }\r
 145                 }\r
 146 \r
 147                 protected override void OnPreRender(EventArgs e)\r
 148                 {\r
 149                         if(Page != null)\r
 150                         {\r
 151                                 Page.RegisterRequiresPostBack(this);\r
 152                         }\r
 153                 }\r
 154 \r
 155                 bool IPostBackDataHandler.LoadPostData(string postDataKey, NameValueCollection postCollection)\r
 156                 {\r
 157                         string xCoord = postCollection[UniqueID + ".x"];\r
 158                         string yCoord = postCollection[UniqueID + ".y"];\r
 159                         if(xCoord != null && yCoord != null && xCoord.Length > 0 && yCoord.Length > 0)\r
 160                         {\r
 161                                 x = Int32.Parse(xCoord);\r
 162                                 y = Int32.Parse(yCoord);\r
 163                                 Page.RegisterRequiresRaiseEvent(this);\r
 164                         }\r
 165                         return false;\r
 166                 }\r
 167 \r
 168                 void IPostBackDataHandler.RaisePostDataChangedEvent()\r
 169                 {\r
 170                 }\r
 171 \r
 172                 void IPostBackEventHandler.RaisePostBackEvent(string eventArgument)\r
 173                 {\r
 174                         if(CausesValidation)\r
 175                                 Page.Validate();\r
 176                         OnClick(new ImageClickEventArgs(x, y));\r
 177                         OnCommand(new CommandEventArgs(CommandName, CommandArgument));\r
 178                 }\r
 179         }\r
 180 }\r