Export (0) Print
Expand All

HtmlInputButton.OnPreRender Method

Raises the OnPreRender event and registers client script for generating postback.

Namespace:  System.Web.UI.HtmlControls
Assembly:  System.Web (in System.Web.dll)

protected internal override void OnPreRender(
	EventArgs e
)

Parameters

e
Type: System.EventArgs

An EventArgs that contains the event data.

The OnPreRender method overrides the Control.OnPreRender method. OnPreRender is used primarily by control developers.

The following code example demonstrates how to override the OnPreRender method so that it always displays a custom HtmlInputButton control with bold text.

<%@ 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 HtmlInputButton - OnPreRender - C# Example</title>
    <script runat="server">
      void Page_Load(Object sender, EventArgs e)
      {
        HtmlInputButton1.Attributes.Add("onclick","alert('Hello client-side world.');");
      }

      void HtmlInputButton1_ServerClick(Object sender, EventArgs e)
      {
        Div1.InnerHtml = "Hello server-side world.";
      }
    </script>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom HtmlInputButton - OnPreRender - C# Example</h3>

      <aspSample:CustomHtmlInputButtonOnPreRender
        id="HtmlInputButton1"
        runat="server"
        type="button"
        onserverclick="HtmlInputButton1_ServerClick"
        value="Html Input Button"
        name="HtmlInputButton1">&nbsp;&nbsp;

      <div id="Div1" runat="server"
        style="DISPLAY: inline; WIDTH: 256px; HEIGHT: 15px" />
    </form>
  </body>
</html>
using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomHtmlInputButtonOnPreRender : System.Web.UI.HtmlControls.HtmlInputButton
    {
        protected override void OnPreRender(System.EventArgs e)
        {
            // Call the base class's OnPreRender method. 
            base.OnPreRender(e);

            // Always display the HtmlInputButton with bold text. 
            this.Style.Add("font-weight", "bold");
        }
    }
}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1
Show:
© 2015 Microsoft