HtmlInputText.OnServerChange(EventArgs) 方法
定义
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。
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
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
在 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。