CustomValidator.ServerValidate Event
Assembly: System.Web (in system.web.dll)
'Declaration Public Event ServerValidate As ServerValidateEventHandler 'Usage Dim instance As CustomValidator Dim handler As ServerValidateEventHandler AddHandler instance.ServerValidate, handler
/** @event */ public void add_ServerValidate (ServerValidateEventHandler value) /** @event */ public void remove_ServerValidate (ServerValidateEventHandler value)
JScript supports the use of events, but not the declaration of new ones.
The ServerValidate event is raised when validation is performed on the server. This event is used to provide a custom validation routine for an input control, such as a TextBox control.
For more information about handling events, see Events and Delegates.
| Topic | Location |
|---|---|
| Walkthrough: Validating User Input in a Web Forms Page | Building ASP .NET Web Applications in Visual Studio |
The following code example demonstrates how to specify and code a handler for a server-side CustomValidator control. It creates a custom validation routine, validates the value of a TextBox control for an even number, and then displays the result of the validation.
<%@ 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="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>
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
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.