ServerValidateEventHandler 委托
表示将处理 CustomValidator 控件的 ServerValidate 事件的方法。
**命名空间:**System.Web.UI.WebControls
**程序集:**System.Web(在 system.web.dll 中)
语法
声明
Public Delegate Sub ServerValidateEventHandler ( _
source As Object, _
args As ServerValidateEventArgs _
)
用法
Dim instance As New ServerValidateEventHandler(AddressOf HandlerMethod)
public delegate void ServerValidateEventHandler (
Object source,
ServerValidateEventArgs args
)
public delegate void ServerValidateEventHandler (
Object^ source,
ServerValidateEventArgs^ args
)
/** @delegate */
public delegate void ServerValidateEventHandler (
Object source,
ServerValidateEventArgs args
)
JScript 支持使用委托,但不支持进行新的声明。
参数
- source
事件源。
- args
包含事件数据的 ServerValidateEventArgs。
备注
使用此委托以提供执行服务器验证的自定义代码。代码需要验证传递给该委托的 args 参数的 Value 属性。在 args 参数的 IsValid 属性中存储验证的结果。
当创建 ServerValidateEventHandler 委托时,将标识处理事件的方法。若要使该事件与事件处理程序相关联,请将该委托的一个实例添加到事件中。除非移除了该委托,否则每当发生该事件时就调用事件处理程序。有关事件处理程序委托的更多信息,请参见 事件和委托。
有关处理事件的更多信息,请参见 使用事件。
示例
下面的示例说明如何指定和编写服务器端 CustomValidator 的处理程序。它显示输入到文本框中的数字是奇数还是偶数。
<%@ Page Language="VB" AutoEventWireup="True" %>
<html>
<head>
<script runat="server">
Sub ValidateBtn_OnClick(sender As Object, e As EventArgs)
' Display whether the page passed validation.
If Page.IsValid Then
Message.Text = "Page is valid."
Else
Message.Text = "Page is not valid!"
End If
End Sub
Sub ServerValidation(source As Object, args As ServerValidateEventArgs)
Try
' Test whether the value entered into the text box is even.
Dim num As Integer = Integer.Parse(args.Value)
args.IsValid = ((num mod 2) = 0)
Catch ex As Exception
args.IsValid = false
End Try
End Sub
</script>
</head>
<body>
<form runat="server">
<h3>CustomValidator ServerValidate Example</h3>
<asp:Label id="Message"
Text="Enter an even number:"
Font-Name="Verdana"
Font-Size="10pt"
runat="server" />
<p>
<asp:TextBox id="Text1"
runat="server" />
<asp:CustomValidator id="CustomValidator1"
ControlToValidate="Text1"
Display="Static"
ErrorMessage="Not an even number!"
ForeColor="green"
Font-Name="verdana"
Font-Size="10pt"
OnServerValidate="ServerValidation"
runat="server"/>
<p>
<asp:Button id="Button1"
Text="Validate"
OnClick="ValidateBtn_OnClick"
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<html>
<head>
<script runat="server">
void ValidateBtn_OnClick(object sender, EventArgs e)
{
// Display whether the page passed validation.
if (Page.IsValid)
{
Message.Text = "Page is valid.";
}
else
{
Message.Text = "Page is not valid!";
}
}
void ServerValidation(object source, ServerValidateEventArgs args)
{
try
{
// Test whether the value entered into the text box is even.
int i = int.Parse(args.Value);
args.IsValid = ((i%2) == 0);
}
catch(Exception ex)
{
args.IsValid = false;
}
}
</script>
</head>
<body>
<form runat="server">
<h3>CustomValidator ServerValidate Example</h3>
<asp:Label id="Message"
Text="Enter an even number:"
Font-Name="Verdana"
Font-Size="10pt"
runat="server"/>
<p>
<asp:TextBox id="Text1"
runat="server" />
<asp:CustomValidator id="CustomValidator1"
ControlToValidate="Text1"
Display="Static"
ErrorMessage="Not an even number!"
ForeColor="green"
Font-Name="verdana"
Font-Size="10pt"
OnServerValidate="ServerValidation"
runat="server"/>
<p>
<asp:Button id="Button1"
Text="Validate"
OnClick="ValidateBtn_OnClick"
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<html>
<head>
<script runat="server">
Sub ValidateBtn_OnClick(sender As Object, e As EventArgs)
' Display whether the page passed validation.
If Page.IsValid Then
Message.Text = "Page is valid."
Else
Message.Text = "Page is not valid!"
End If
End Sub
Sub ServerValidation(source As Object, args As ServerValidateEventArgs)
Try
' Test whether the value entered into the text box is even.
Dim num As Integer = Integer.Parse(args.Value)
args.IsValid = ((num mod 2) = 0)
Catch ex As Exception
args.IsValid = false
End Try
End Sub
Sub Page_Load(sende As object, e As EventArgs)
' Manually register the event-handling method for the
' ServerValidate event of the CustomValidator control.
AddHandler CustomValidator1.ServerValidate, _
AddressOf ServerValidation
End Sub
</script>
</head>
<body>
<form runat="server">
<h3>CustomValidator ServerValidate Example</h3>
<asp:Label id="Message"
Text="Enter an even number:"
Font-Name="Verdana"
Font-Size="10pt"
runat="server" />
<p>
<asp:TextBox id="Text1"
runat="server" />
<asp:CustomValidator id="CustomValidator1"
ControlToValidate="Text1"
Display="Static"
ErrorMessage="Not an even number!"
ForeColor="green"
Font-Name="verdana"
Font-Size="10pt"
runat="server"/>
<p>
<asp:Button id="Button1"
Text="Validate"
OnClick="ValidateBtn_OnClick"
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<html>
<head>
<script runat="server">
void ValidateBtn_OnClick(object sender, EventArgs e)
{
// Display whether the page passed validation.
if (Page.IsValid)
{
Message.Text = "Page is valid.";
}
else
{
Message.Text = "Page is not valid!";
}
}
void ServerValidation(object source, ServerValidateEventArgs args)
{
try
{
// Test whether the value entered into the text box is even.
int i = int.Parse(args.Value);
args.IsValid = ((i%2) == 0);
}
catch(Exception ex)
{
args.IsValid = false;
}
}
void Page_Load(object sender, EventArgs e)
{
// Manually register the event-handling method for the
// ServerValidate event of the CustomValidator control.
CustomValidator1.ServerValidate +=
new ServerValidateEventHandler(this.ServerValidation);
}
</script>
</head>
<body>
<form runat="server">
<h3>CustomValidator ServerValidate Example</h3>
<asp:Label id="Message"
Text="Enter an even number:"
Font-Name="Verdana"
Font-Size="10pt"
runat="server"/>
<p>
<asp:TextBox id="Text1"
runat="server" />
<asp:CustomValidator id="CustomValidator1"
ControlToValidate="Text1"
Display="Static"
ErrorMessage="Not an even number!"
ForeColor="green"
Font-Name="verdana"
Font-Size="10pt"
runat="server"/>
<p>
<asp:Button id="Button1"
Text="Validate"
OnClick="ValidateBtn_OnClick"
runat="server"/>
</form>
</body>
</html>
平台
Windows 98、Windows 2000 SP4、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表,请参见系统要求。
版本信息
.NET Framework
受以下版本支持:2.0、1.1、1.0