Membership.ValidateUser Method

Verifies that the supplied user name and password are valid.

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

public static bool ValidateUser(
	string username,
	string password
)

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.

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 null, an HttpException is thrown.

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 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.

<%@ 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 xmlns="http://www.w3.org/1999/xhtml" >
<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>

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0
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