FormsAuthentication.RedirectToLoginPage Method (String)
.NET Framework (current version)
Redirects the browser to the login URL with the specified query string.
Assembly: System.Web (in System.Web.dll)
Parameters
- extraQueryString
-
Type:
System.String
The query string to include with the redirect URL.
The RedirectToLoginPage method redirects the browser to the LoginUrl and includes the extraQueryString value as the QueryString for the redirected URL.
The RedirectToLoginPage method does not clear the forms-authentication cookie. You can use the RedirectToLoginPage method in conjunction with the SignOut method to log one user out and allow a different user to log in.
The following code example clears the forms-authentication cookie using the SignOut method and redirects the user to the login page using the RedirectToLoginPage method.
<%@ Page Language="VB" %> <%@ Import Namespace="System.Web.Security" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> Public Sub LoginLink_OnClick(sender As Object, args As EventArgs) FormsAuthentication.SignOut() FormsAuthentication.RedirectToLoginPage(GetQueryString()) End Sub Private Function GetQueryString() As String Dim queryString As String = "" Dim qs As NameValueCollection = Request.QueryString For Each key As String In qs.AllKeys For Each value As String In qs.GetValues(key) queryString &= Server.UrlEncode(key) & "=" & Server.UrlEncode(value) & "&" Next Next Return queryString.TrimEnd("&") End Function </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>ASP.NET Example</title> </head> <body> <form id="form1" runat="server"> Welcome <b><%=User.Identity.Name%></b>. Not <b><%=User.Identity.Name%></b>? Click <asp:LinkButton id="LoginLink" Text="here" OnClick="LoginLink_OnClick" runat="server" /> to sign in. <!-- Page Contents --> </form> </body> </html>
.NET Framework
Available since 2.0
Available since 2.0
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