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LoginCancelEventArgs Class

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Provides data for a cancelable event.

public ref class LoginCancelEventArgs : EventArgs
public class LoginCancelEventArgs : EventArgs
type LoginCancelEventArgs = class
    inherit EventArgs
Public Class LoginCancelEventArgs
Inherits EventArgs
Inheritance
Object
EventArgs
LoginCancelEventArgs
Derived

Examples

The following code example uses the LoggingIn event to ensure that the user has entered a well-formed email address in the UserName property. If not, the LoggingIn event handler cancels the logon attempt by setting the Cancel property of the LoginCancelEventArgs object to true.Then the error message specified in the InstructionText property is displayed.

public partial class LoginCancelEventArgscs_aspx : System.Web.UI.Page
{

    bool IsValidEmail(string strIn)
    {
        // Return true if strIn is in valid email format.
        return System.Text.RegularExpressions.Regex.IsMatch(strIn, 
            @"^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$");
    }
    
    protected void OnLoggingIn(object sender, System.Web.UI.WebControls.LoginCancelEventArgs e)
    {
        if (!IsValidEmail(Login1.UserName))
        {
            Login1.InstructionText = "You must enter a valid email address.";
            e.Cancel = true;
        }
        else
        {
            Login1.InstructionText = String.Empty;
        }
    }
}

Partial Class LoginCancelEventArgsvb_aspx
    Inherits System.Web.UI.Page

    Function IsValidEmail(ByVal strIn As String) As Boolean
        ' Return true if strIn is in valid email format.
        Return Regex.IsMatch(strIn, _
            ("^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$"))
    End Function

    Protected Sub OnLoggingIn(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.LoginCancelEventArgs)
        If Not IsValidEmail(Login1.UserName) Then
            Login1.InstructionText = "You must enter a valid email address."
            e.Cancel = True
        Else
            Login1.InstructionText = String.Empty
        End If
    End Sub

End Class

The following is the .aspx file that can be used to run the preceding example.

<%@ Page Language="C#" CodeFile="LoginCancelEventArgs.cs" Inherits="LoginCancelEventArgscs_aspx" %>

<!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 runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
        <form id="Form1" runat="server">
            <asp:Login id="Login1" 
              runat="server" 
              onloggingin="OnLoggingIn">
            </asp:Login>
        </form>
    </body>
</html>

<%@ Page Language="VB" AutoEventWireup="false" CodeFile="LoginCancelEventArgs.vb" Inherits="LoginCancelEventArgsvb_aspx" %>

<!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 runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
        <form id="Form1" runat="server">
            <asp:Login id="Login1" 
              runat="server" 
              onloggingin="OnLoggingIn">
            </asp:Login>
        </form>
    </body>
</html>

Remarks

A cancelable event is raised when a component is about to perform an action that can be canceled, such as logging on to a Web site.

The LoginCancelEventArgs class provides the Cancel property to indicate whether the event should be canceled. A LoginCancelEventArgs object is used with controls that have cancelable actions, such as the Login control, the CreateUserWizard control, and the PasswordRecovery control.

Constructors

LoginCancelEventArgs()

Initializes a new instance of the LoginCancelEventArgs class with the Cancel property set to false.
LoginCancelEventArgs(Boolean)

Initializes a new instance of the LoginCancelEventArgs class with the Cancel property set to the specified value.

Properties

Cancel

Gets or sets a value indicating whether the event should be canceled.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also