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FormsAuthentication.Encrypt Method

Creates a string containing an encrypted forms-authentication ticket suitable for use in an HTTP cookie.

Namespace: System.Web.Security
Assembly: System.Web (in system.web.dll)

'Declaration
Public Shared Function Encrypt ( _
	ticket As FormsAuthenticationTicket _
) As String
'Usage
Dim ticket As FormsAuthenticationTicket
Dim returnValue As String

returnValue = FormsAuthentication.Encrypt(ticket)
public static String Encrypt (
	FormsAuthenticationTicket ticket
)
public static function Encrypt (
	ticket : FormsAuthenticationTicket
) : String
Not applicable.

Parameters

ticket

The FormsAuthenticationTicket object with which to create the encrypted forms-authentication ticket.

Return Value

A string containing an encrypted forms-authentication ticket.

Exception typeCondition

ArgumentNullException

ticket is a null reference (Nothing in Visual Basic).

The following code example stores the result of the Encrypt method in a cookie by using the FormsCookieName property and redirects the user to the URL returned from the GetRedirectUrl method.

Security noteSecurity Note:

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 (Visual Studio).

<%@ 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 = PersistCheckBox.Checked

    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>
                <tr>
                    <td>Check here if this is
                        <span style="text-decoration:underline"> not </span>
                        <br />a public computer:</td>
                    <td><asp:CheckBox id="PersistCheckBox" runat="server" autopostback="true" /></td>
                </tr>
            </tbody>
        </table>
        <input type="submit" value="Login" runat="server" onserverclick="Login_Click" />
    </form>
</body>
</html>

Windows 98, Windows Server 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0
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