Membership.ValidateUser Method (System.Web.Security)

ValidateUser Method

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This page is specific to

Microsoft Visual Studio 2008/.NET Framework 3.5

Other versions are also available for the following:

.NET Framework Class Library

Membership..::.ValidateUser Method

Verifies that the supplied user name and password are valid.

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

Syntax

Visual Basic (Declaration)

Public Shared Function ValidateUser ( _
    username As String, _
    password As String _
) As Boolean

Visual Basic (Usage)

Dim username As String
Dim password As String
Dim returnValue As Boolean

returnValue = Membership.ValidateUser(username, _
    password)

public static bool ValidateUser(
    string username,
    string password
)

Visual C++

public:
static bool ValidateUser(
    String^ username, 
    String^ password
)

JScript

public static function ValidateUser(
    username : String, 
    password : String
) : boolean

Parameters

username: Type: System..::.String
The name of the user to be validated.

password: Type: System..::.String
The password for the specified user.

Return Value

Type: System..::.Boolean
true if the supplied user name and password are valid; otherwise, false.

Remarks

ValidateUser provides an easy way to verify a user name and password from the data source. Note that, if the username parameter is empty or nullNothingnullptra null reference (Nothing in Visual Basic), an HttpException is thrown.

Examples

The following code example shows the login page for an ASP.NET application configured to use forms authentication and the Membership class. If the supplied user credentials are invalid, a message is displayed to the user. Otherwise, the user is redirected to the originally requested URL by the RedirectFromLoginPage method.

Security 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 Basic

<%@ 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 Login_OnClick(sender As Object, args As  EventArgs)

   If (Membership.ValidateUser(UsernameTextbox.Text, PasswordTextbox.Text)) Then
      FormsAuthentication.RedirectFromLoginPage(UsernameTextbox.Text, NotPublicCheckBox.Checked)
   Else
     Msg.Text = "Login failed. Please check your user name and password and try again."
   End If

End Sub

</script>

<html  >
<head>
  <title>Login</title>
</head>
<body>

<form id="form1" runat="server">
  <h3>Login</h3>

  <asp:Label id="Msg" ForeColor="maroon" runat="server" /><br />

  Username: <asp:Textbox id="UsernameTextbox" runat="server" /><br />
  Password: <asp:Textbox id="PasswordTextbox" runat="server" TextMode="Password" /><br />

  <asp:Button id="LoginButton" Text="Login" OnClick="Login_OnClick" runat="server" />
  <asp:CheckBox id="NotPublicCheckBox" runat="server" /> 
  Check here if this is <span style="text-decoration:underline">not</span> a public computer.

</form>

</body>
</html>

<%@ 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 Login_OnClick(object sender, EventArgs args)
{
   if (Membership.ValidateUser(UsernameTextbox.Text, PasswordTextbox.Text))
      FormsAuthentication.RedirectFromLoginPage(UsernameTextbox.Text, NotPublicCheckBox.Checked);
   else
     Msg.Text = "Login failed. Please check your user name and password and try again.";
}


</script>

<html  >
<head>
  <title>Login</title>
</head>
<body>

<form id="form1" runat="server">
  <h3>Login</h3>

  <asp:Label id="Msg" ForeColor="maroon" runat="server" /><br />

  Username: <asp:Textbox id="UsernameTextbox" runat="server" /><br />
  Password: <asp:Textbox id="PasswordTextbox" runat="server" TextMode="Password" /><br />

  <asp:Button id="LoginButton" Text="Login" OnClick="Login_OnClick" runat="server" />
  <asp:CheckBox id="NotPublicCheckBox" runat="server" /> 
  Check here if this is <span style="text-decoration:underline">not</span> a public computer.

</form>

</body>
</html>

Platforms

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

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information