HtmlInputText.OnServerChange(EventArgs) 方法

定义

引发 ServerChange 事件。

protected:
 virtual void OnServerChange(EventArgs ^ e);
protected virtual void OnServerChange (EventArgs e);
abstract member OnServerChange : EventArgs -> unit
override this.OnServerChange : EventArgs -> unit
Protected Overridable Sub OnServerChange (e As EventArgs)

参数

e
EventArgs

包含事件数据的 EventArgs

示例

下面的代码示例演示如何为 ServerChange 事件指定和编码处理程序。 自定义事件处理程序更新网页上的标签,以显示输入到 HTML 元素中的 <input type=text> 文本值。


<%@ 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>HtmlInputText ServerChange Example</title>
<script runat="server">

      void Server_Change(object sender, EventArgs e) 
      {
         Span1.InnerHtml = "You typed: " + Text1.Value;
      }

      void Page_Load(object sender, EventArgs e)
      {
         // Create an EventHandler delegate for the method you want to
         // handle the event, and then add it to the list of methods
         // called when the event is raised.
         Text1.ServerChange += new System.EventHandler(this.Server_Change);
      }         

   </script>

</head>

<body>

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

      <h3>HtmlInputText ServerChange Example</h3>

      Enter a value in the input field below and 
      click the Submit button.

      <br />

      <input type="text" 
             id="Text1" 
             runat="server"/>
      <br />

      <br />

      <input type="submit" 
             id="Button1" 
             value="Submit" 
             runat="server"/>

      <br />

      <span id="Span1" 
            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>HtmlInputText ServerChange Example</title>
<script runat="server">

     Sub Server_Change(ByVal sender As Object, ByVal e As EventArgs)

       Span1.InnerHtml = String.Format("You typed: {0}", Text1.Value)

     End Sub

     Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

       ' Create an EventHandler delegate for the method you want to
       ' handle the event, and then add it to the list of methods
       ' called when the event is raised.
       AddHandler Text1.ServerChange, AddressOf Server_Change
      
     End Sub

   </script>

</head>

<body>

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

      <h3>HtmlInputText ServerChange Example</h3>

      Enter a value in the input field below and 
      click the Submit button.

      <br />

      <input type="text" 
             id="Text1" 
             runat="server"/>
      <br />

      <input type="submit" 
             id="Button1" 
             value="Submit" 
             runat="server"/>

      <br />

      <span id="Span1" 
            runat="server" />

   </form>

</body>
</html>

注解

ServerChange 服务器上更改 属性时 Value ,将引发 事件。

注意

控件必须启用视图状态, ServerChange 事件才能正常工作。

引发事件时,将通过委托调用事件处理程序。 有关详细信息,请参阅 处理和引发事件

OnServerChange 方法还允许派生类对事件进行处理而不必附加委托。 这是在派生类中处理事件的首选技术。

继承者说明

在派生类中重写 OnServerChange(EventArgs) 时,一定要调用基类的 OnServerChange(EventArgs) 方法,以便已注册的委托对事件进行接收。

适用于

另请参阅