تحرير

مشاركة عبر

LinkButton.OnPreRender(EventArgs) Method

  • Reference

Definition

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

Raises the PreRender event.

protected:
 override void OnPreRender(EventArgs ^ e);
protected public:
 override void OnPreRender(EventArgs ^ e);
protected override void OnPreRender (EventArgs e);
protected internal override void OnPreRender (EventArgs e);
override this.OnPreRender : EventArgs -> unit
Protected Overrides Sub OnPreRender (e As EventArgs)
Protected Friend Overrides Sub OnPreRender (e As EventArgs)

Parameters

e
EventArgs

An EventArgs object that contains the event data.

Examples

The following code example demonstrates how to override the OnPreRender method so that a border is never displayed in a custom LinkButton control.

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<%@ 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>Custom LinkButton - OnPreRender - C# Example</title>
    <script runat="server">
      void LinkButton1_Command(Object sender, CommandEventArgs e) 
      {
        // Redirect to the Microsoft home page.
        Response.Redirect("http://www.microsoft.com/");
      }
    </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom LinkButton - OnPreRender - C# Example</h3>
            
            <aspSample:CustomLinkButtonOnPreRender 
              id="LinkButton1" 
              runat="server" 
              OnCommand="LinkButton1_Command" 
              ToolTip="Microsoft Home">Microsoft Corp.
            </aspSample:CustomLinkButtonOnPreRender>
            
        </form>
    </body>
</html>

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<%@ 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>Custom LinkButton - OnPreRender - VB.NET Example</title>
        <script runat="server">
            Sub LinkButton1_Command(sender As Object, e As CommandEventArgs)
                ' Redirect to the Microsoft home page.
                Response.Redirect("http://www.microsoft.com/")
            End Sub
        </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom LinkButton - OnPreRender - VB.NET Example</h3>
            
            <aspSample:CustomLinkButtonOnPreRender id="LinkButton1" 
             runat="server" OnCommand="LinkButton1_Command" 
             ToolTip="Microsoft Home">Microsoft Corp.</aspSample:CustomLinkButtonOnPreRender>

        </form>
    </body>
</html>

using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand, Level=AspNetHostingPermissionLevel.Minimal)]
  public sealed class CustomLinkButtonOnPreRender : System.Web.UI.WebControls.LinkButton
  {
    protected override void OnPreRender(System.EventArgs e)
    {
      // Run the OnPreRender method on the base class.
      base.OnPreRender(e);

      // Always display the LinkButton without a border.
      this.BorderWidth =  System.Web.UI.WebControls.Unit.Point(0);
    }
  }
}

<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomLinkButtonOnPreRender
    Inherits System.Web.UI.WebControls.LinkButton

    Protected Overrides Sub OnPreRender(ByVal e As System.EventArgs)

        ' Run the OnPreRender method on the base class.
        MyBase.OnPreRender(e)

        ' Always display the LinkButton without a border.
        Me.BorderWidth = System.Web.UI.WebControls.Unit.Point(0)
    End Sub
End Class

Remarks

The OnPreRender method notifies the LinkButton control to perform any necessary prerendering steps prior to saving view state and rendering content to the client.

Applies to

See also