FormsAuthentication.RedirectToLoginPage Method
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Redirects the browser to the login URL.
Overloads
| RedirectToLoginPage() |
Redirects the browser to the login URL. |
| RedirectToLoginPage(String) |
Redirects the browser to the login URL with the specified query string. |
Examples
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="C#" %>
<%@ 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 void LoginLink_OnClick(object sender, EventArgs args)
{
FormsAuthentication.SignOut();
FormsAuthentication.RedirectToLoginPage();
}
</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>
<%@ 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()
End Sub
</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>
Remarks
The RedirectToLoginPage method redirects the browser to the LoginUrl.
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.
Unlike the HttpResponse.Redirect method, this method does not end the request by calling HttpResponse.End. This means that code that follows the RedirectToLoginPage method call will run.
RedirectToLoginPage()
Redirects the browser to the login URL.
public:
static void RedirectToLoginPage();public static void RedirectToLoginPage ();static member RedirectToLoginPage : unit -> unitPublic Shared Sub RedirectToLoginPage ()Examples
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="C#" %>
<%@ 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 void LoginLink_OnClick(object sender, EventArgs args)
{
FormsAuthentication.SignOut();
FormsAuthentication.RedirectToLoginPage();
}
</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>
<%@ 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()
End Sub
</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>
Remarks
The RedirectToLoginPage method redirects the browser to the LoginUrl.
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.
See also
Applies to
RedirectToLoginPage(String)
Redirects the browser to the login URL with the specified query string.
public:
static void RedirectToLoginPage(System::String ^ extraQueryString);public static void RedirectToLoginPage (string extraQueryString);static member RedirectToLoginPage : string -> unitPublic Shared Sub RedirectToLoginPage (extraQueryString As String)Parameters
- extraQueryString
- String
The query string to include with the redirect URL.
Examples
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="C#" %>
<%@ 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 void LoginLink_OnClick(object sender, EventArgs args)
{
FormsAuthentication.SignOut();
FormsAuthentication.RedirectToLoginPage(GetQueryString());
}
private string GetQueryString()
{
string queryString = "";
NameValueCollection qs = Request.QueryString;
foreach (string key in qs.AllKeys)
foreach (string value in qs.GetValues(key))
queryString += Server.UrlEncode(key) + "=" + Server.UrlEncode(value) + "&";
return queryString.TrimEnd('&');
}
</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>
<%@ 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>
Remarks
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.
