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HtmlInputCheckBox.ServerChange Event

  • Reference

Definition

Namespace:
System.Web.UI.HtmlControls
Assembly:
System.Web.dll

Occurs when the Web page is submitted to the server and the HtmlInputCheckBox control changes state from the previous post.

public:
 event EventHandler ^ ServerChange;
public event EventHandler ServerChange;
member this.ServerChange : EventHandler 
Public Custom Event ServerChange As EventHandler

Event Type

EventHandler

Examples

The following code example demonstrates how to specify and code a handler for the ServerChange event.

<%@ Page Language="C#" AutoEventWireup="True" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>HtmlInputCheckBox Sample</title>
<script language="C#" runat="server">

      void Button1_Click(object sender, EventArgs e) 
      { 

         if (Prev_Check_State.Value == Check1.Checked.ToString())
            Span2.InnerHtml = "CheckBox1 did not change state between clicks.";

         if (Check1.Checked == true)
         {          
            Span1.InnerHtml = "CheckBox1 is selected!";
            Prev_Check_State.Value="True";
         }         
         else
         { 
            Span1.InnerHtml = "CheckBox1 is not selected!";
            Prev_Check_State.Value="False";
         }
         
      }

      void Server_Changed(object sender, EventArgs e) 
      {
         Span2.InnerHtml = "CheckBox1 changed state between clicks.";
      }

   </script>

</head>

<body>

   <h3>HtmlInputCheckBox Sample</h3>

   <form id="form1" runat="server">

      <input id="Check1" 
             type="checkbox"
             onserverchange="Server_Changed" 
             runat="server"/> 
 
      CheckBox1   

      <span id="Span1" 
            style="color:red" 
            runat="server"/>

      <br />

      <input type="button" 
             id="Button1" 
             value="Enter" 
             onserverclick="Button1_Click" 
             runat="server"/>
      
      <br /><br />

      <span id="Span2" 
            runat="server"/>

      <input type="hidden" id="Prev_Check_State"
                       visible="false"
                       runat="server"/>

   </form>

</body>
</html>

<%@ Page Language="VB" AutoEventWireup="True" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>HtmlInputCheckBox Sample</title>
<script language="VB" runat="server">

    Sub Button1_Click(sender As Object, e As EventArgs)
        
        If Prev_Check_State.Value = Check1.Checked.ToString() Then
            Span2.InnerHtml = "CheckBox1 did not change state between clicks."
        End If
        If Check1.Checked = True Then
            Span1.InnerHtml = "CheckBox1 is selected!"
            Prev_Check_State.Value = "True"
        Else
            Span1.InnerHtml = "CheckBox1 is not selected!"
            Prev_Check_State.Value = "False"
        End If
    End Sub 'Button1_Click
     

    Sub Server_Changed(sender As Object, e As EventArgs)
        Span2.InnerHtml = "CheckBox1 changed state between clicks."
    End Sub 'Server_Changed

  </script>

</head>

<body>

   <h3>HtmlInputCheckBox Sample</h3>

   <form id="form1" runat="server">

      <input id="Check1" 
             type="checkbox"
             onserverchange="Server_Changed" 
             runat="server"/> 
 
      CheckBox1   

      <span id="Span1" 
            style="color:red" 
            runat="server"/>

      <br />

      <input type="button" 
             id="Button1" 
             value="Enter" 
             onserverclick="Button1_Click" 
             runat="server"/>
      
      <br /><br />

      <span id="Span2" 
            runat="server"/>

      <input type="hidden" id="Prev_Check_State"
                       visible="false"
                       runat="server"/>
   </form>

</body>
</html>

Remarks

This event is raised when the Web page is submitted to the server and the HtmlInputCheckBox control changes state from the previous post.

Note

The control must have view state enabled for the ServerChange event to work correctly.

For more information about how to handle events, see Handling and Raising Events.

Applies to

See also