FormsAuthentication.RedirectToLoginPage Method

Reference

Definition

Namespace:: System.Web.Security

Assembly:: System.Web.dll

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 -> unit

Public 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.

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 -> unit

Public 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.

Applies to

Kongsi melalui

FormsAuthentication.RedirectToLoginPage Method

Definition

Overloads

Examples

Remarks

RedirectToLoginPage()

Examples

Remarks

See also

Applies to

RedirectToLoginPage(String)

Parameters

Examples

Remarks

See also

Applies to

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