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FormsAuthentication.GetRedirectUrl(String, Boolean) Method

Definition

Returns the redirect URL for the original request that caused the redirect to the login page.

public:
 static System::String ^ GetRedirectUrl(System::String ^ userName, bool createPersistentCookie);
public static string GetRedirectUrl (string userName, bool createPersistentCookie);
static member GetRedirectUrl : string * bool -> string
Public Shared Function GetRedirectUrl (userName As String, createPersistentCookie As Boolean) As String

Parameters

userName
String

The name of the authenticated user.

createPersistentCookie
Boolean

This parameter is ignored.

Returns

A string that contains the redirect URL, or null if userName is null.

Examples

The following code example redirects authenticated users to the URL returned from the GetRedirectUrl method.

Important

This example contains a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

<%@ 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">

  private void Login_Click(Object sender, EventArgs e)
  {
    // Create a custom FormsAuthenticationTicket containing
    // application specific data for the user.

    string username     = UserNameTextBox.Text;
    string password     = UserPassTextBox.Text;
    bool   isPersistent = false;

    if (Membership.ValidateUser(username, password))
    {
      string userData = "ApplicationSpecific data for this user.";

      FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(1,
        username,
        DateTime.Now,
        DateTime.Now.AddMinutes(30),
        isPersistent,
        userData,
        FormsAuthentication.FormsCookiePath);

      // Encrypt the ticket.
      string encTicket = FormsAuthentication.Encrypt(ticket);

      // Create the cookie.
      Response.Cookies.Add(new HttpCookie(FormsAuthentication.FormsCookieName, encTicket));

      // Redirect back to original URL.
      Response.Redirect(FormsAuthentication.GetRedirectUrl(username, isPersistent));
    }
    else
    {
      Msg.Text = "Login failed. Please check your user name and password and try again.";
    }
  }

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>Forms Authentication Login</title>
</head>
<body>
    <form id="form1" runat="server">
        <span style="BACKGROUND: #80ff80; font-weight:bold"> 
            Login Page
        </span> 
        <asp:Label id="Msg" ForeColor="maroon" runat="server" /><br />
        <table border="0">
            <tbody>
                <tr>
                    <td>Username:</td>
                    <td><asp:TextBox id="UserNameTextBox" runat="server" /></td>
                    <td>
                      <asp:RequiredFieldValidator id="RequiredFieldValidator1" 
                                                  runat="server" ErrorMessage="*" 
                                                  Display="Static" 
                                                  ControlToValidate="UserNameTextBox" />
                    </td>
                </tr>
                <tr>
                    <td>Password:</td>
                    <td><asp:TextBox id="UserPassTextBox" TextMode="Password" runat="server" /></td>
                    <td>
                      <asp:RequiredFieldValidator id="RequiredFieldValidator2" 
                                                  runat="server" ErrorMessage="*" 
                                                  Display="Static" 
                                                  ControlToValidate="UserPassTextBox" />
                    </td>
                </tr>
            </tbody>
        </table>
        <input type="submit" value="Login" runat="server" onserverclick="Login_Click" />
    </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">

  Private Sub Login_Click(sender As Object, e As EventArgs)
  
    ' Create a custom FormsAuthenticationTicket containing
    ' application specific data for the user.

        Dim username As String = UserNameTextBox.Text
        Dim password As String = UserPassTextBox.Text
        Dim isPersistent As Boolean = False

    If Membership.ValidateUser(username, password) Then
    
      Dim userData As String = "ApplicationSpecific data for this user."

      Dim ticket As FormsAuthenticationTicket = New FormsAuthenticationTicket(1, _
        username, _
        DateTime.Now, _
        DateTime.Now.AddMinutes(30), _
        isPersistent, _
        userData, _
        FormsAuthentication.FormsCookiePath)

      ' Encrypt the ticket.
      Dim encTicket As String = FormsAuthentication.Encrypt(ticket)

      ' Create the cookie.
      Response.Cookies.Add(New HttpCookie(FormsAuthentication.FormsCookieName, encTicket))

      ' Redirect back to original URL.
      Response.Redirect(FormsAuthentication.GetRedirectUrl(username, isPersistent))
    Else    
      Msg.Text = "Login failed. Please check your user name and password and try again."
    End If
  End Sub

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>Forms Authentication Login</title>
</head>
<body>
    <form id="form1" runat="server">
        <span style="BACKGROUND:#80ff80; font-weight:bold"> 
          Login Page
        </span> 
        <asp:Label id="Msg" ForeColor="maroon" runat="server" /><br />
        <table border="0">
            <tbody>
                <tr>
                    <td>Username:</td>
                    <td><asp:TextBox id="UserNameTextBox" runat="server" /></td>
                    <td>
                      <asp:RequiredFieldValidator id="RequiredFieldValidator1" 
                                                  runat="server" ErrorMessage="*" 
                                                  Display="Static" 
                                                  ControlToValidate="UserNameTextBox" />
                    </td>
                </tr>
                <tr>
                    <td>Password:</td>
                    <td><asp:TextBox id="UserPassTextBox" TextMode="Password" runat="server" /></td>
                    <td>
                      <asp:RequiredFieldValidator id="RequiredFieldValidator2" 
                                                  runat="server" ErrorMessage="*" 
                                                  Display="Static" 
                                                  ControlToValidate="UserPassTextBox" />
                    </td>
                </tr>
            </tbody>
        </table>
        <input type="submit" value="Login" runat="server" onserverclick="Login_Click" />
    </form>
</body>
</html>

Remarks

You can use this method when you want to perform the redirect in your application code instead of using the RedirectFromLoginPage method.

The GetRedirectUrl method returns the URL specified in the query string using the ReturnURL variable name. For example, in the URL http://www.contoso.com/login.aspx?ReturnUrl=caller.aspx, the GetRedirectUrl method returns the return URL caller.aspx. If the ReturnURL variable does not exist, the GetRedirectUrl method returns the URL in the DefaultUrl property.

ASP.NET automatically adds the return URL when the browser is redirected to the login page.

By default, the ReturnUrl variable must refer to a page within the current application. If ReturnUrl refers to a page in a different application or on a different server, the GetRedirectUrl methods returns the URL in the DefaultUrl property. If you want to allow the return URL to refer to a page outside the current application, you must set the EnableCrossAppRedirects property to true using the enableCrossAppRedirects attribute of the forms configuration element.

This method does not create a cookie.

Important

Setting the EnableCrossAppRedirects property to true to allow cross-application redirects is a potential security threat. For more information, see the EnableCrossAppRedirects property.

Applies to

See also