IPostBackEventHandler 接口
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
定义 ASP.NET 服务器控件为处理回发事件而必须实现的方法。
public interface class IPostBackEventHandlerpublic interface IPostBackEventHandlertype IPostBackEventHandler = interfacePublic Interface IPostBackEventHandler- 派生
下面的代码示例定义一个自定义按钮服务器控件，该控件会导致回发，使用 RaisePostBackEvent 方法捕获回发事件，并在服务器上引发 事件 Click 。
using System;
using System.Web.UI;
using System.Collections;
using System.Collections.Specialized;
namespace CustomControls {
[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
public class MyButton: Control, IPostBackEventHandler {
// Defines the Click event.
public event EventHandler Click;
//Invoke delegates registered with the Click event.
protected virtual void OnClick(EventArgs e) {
if (Click != null) {
Click(this, e);
}
}
// Define the method of IPostBackEventHandler that raises change events.
public void RaisePostBackEvent(string eventArgument){
OnClick(new EventArgs());
}
protected override void Render(HtmlTextWriter output) {
output.Write("<INPUT TYPE = submit name = " + this.UniqueID +
" Value = 'Click Me' />");
}
}
}
Imports System.Web.UI
Imports System.Collections
Imports System.Collections.Specialized
Namespace CustomControls
<System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> Public Class MyButton
Inherits Control
Implements IPostBackEventHandler
' Define the Click event.
Public Event Click As EventHandler
' Invoke delegates registered with the Click event.
Protected Overridable Sub OnClick(e As EventArgs)
RaiseEvent Click(Me, e)
End Sub
' Define the method of IPostBackEventHandler that raises change events.
Public Sub RaisePostBackEvent(eventArgument As String) _
Implements IPostBackEventHandler.RaisePostBackEvent
OnClick(New EventArgs())
End Sub
Protected Overrides Sub Render(output As HtmlTextWriter)
output.Write("<INPUT TYPE = submit name = " & Me.UniqueID & _
" Value = 'Click Me' />")
End Sub
End Class
End Namespace
若要创建从浏览器捕获表单提交信息的服务器控件，必须实现此接口。 有关如何使用此接口的详细信息，请参阅 ASP.NET Web 窗体页中的服务器事件处理。
|
Raise |
当由类实现时，使服务器控件能够处理将窗体发送到服务器时引发的事件。 |
| 产品 | 版本 |
|---|---|
| .NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
