Membership.RequiresQuestionAndAnswer Property

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.

Gets a value indicating whether the default membership provider requires the user to answer a password question for password reset and retrieval.

public:
 static property bool RequiresQuestionAndAnswer { bool get(); };

public static bool RequiresQuestionAndAnswer { get; }

static member RequiresQuestionAndAnswer : bool

Public Shared ReadOnly Property RequiresQuestionAndAnswer As Boolean

Property Value

Boolean

true if a password answer is required for password reset and retrieval; otherwise, false.

Examples

The following code example shows the membership element in the system.web section of the Web.config file for an ASP.NET application. It specifies that the application use an instance of the SqlMembershipProvider, enables password reset, and requires a password answer when performing a reset.

<membership defaultProvider="SqlProvider" userIsOnlineTimeWindow="20">  
  <providers>  
    <add name="SqlProvider"  
      type="System.Web.Security.SqlMembershipProvider"  
      connectionStringName="SqlServices"  
      enablePasswordRetrieval="false"  
      enablePasswordReset="true"  
      requiresQuestionAndAnswer="true"  
      passwordFormat="Hashed"  
      applicationName="MyApplication" />  
  </providers>  
</membership>

The following code sample checks the value of RequiresQuestionAndAnswer and adds the necessary controls for a password question and answer to be supplied when creating a user.

Important

This example includes 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 CreateUser_OnClick(object sender, EventArgs args)
{
  // Create new user and retrieve create status result.

  MembershipCreateStatus status;
  string passwordQuestion = "";
  string passwordAnswer = "";

  if (Membership.RequiresQuestionAndAnswer)
  {
    passwordQuestion = PasswordQuestionTextbox.Text;
    passwordAnswer = PasswordAnswerTextbox.Text;
  }

  try
  {
    MembershipUser newUser = Membership.CreateUser(UsernameTextbox.Text, PasswordTextbox.Text, 
                                                   EmailTextbox.Text, passwordQuestion,
                                                   passwordAnswer, true, out status);
    if (newUser == null)
    {
      Msg.Text = GetErrorMessage(status);
    }
    else
    {
      Response.Redirect("login.aspx");
    }
  }
  catch
  {
    Msg.Text = "An exception occurred creating the user.";
  }
}

public string GetErrorMessage(MembershipCreateStatus status)
{
   switch (status)
   {
      case MembershipCreateStatus.DuplicateUserName:
        return "Username already exists. Please enter a different user name.";

      case MembershipCreateStatus.DuplicateEmail:
        return "A username for that email address already exists. Please enter a different email address.";

      case MembershipCreateStatus.InvalidPassword:
        return "The password provided is invalid. Please enter a valid password value.";

      case MembershipCreateStatus.InvalidEmail:
        return "The email address provided is invalid. Please check the value and try again.";

      case MembershipCreateStatus.InvalidAnswer:
        return "The password retrieval answer provided is invalid. Please check the value and try again.";

      case MembershipCreateStatus.InvalidQuestion:
        return "The password retrieval question provided is invalid. Please check the value and try again.";

      case MembershipCreateStatus.InvalidUserName:
        return "The user name provided is invalid. Please check the value and try again.";

      case MembershipCreateStatus.ProviderError:
        return "The authentication provider returned an error. Please verify your entry and try again. If the problem persists, please contact your system administrator.";

      case MembershipCreateStatus.UserRejected:
        return "The user creation request has been canceled. Please verify your entry and try again. If the problem persists, please contact your system administrator.";

      default:
        return "An unknown error occurred. Please verify your entry and try again. If the problem persists, please contact your system administrator.";
   }
}

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>Create User</title>
</head>
<body>

<form id="form1" runat="server">
  <h3>Create New User</h3>

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

  <table cellpadding="3" border="0">
    <tr>
      <td>Username:</td>
      <td><asp:Textbox id="UsernameTextbox" runat="server" /></td>
      <td><asp:RequiredFieldValidator id="UsernameRequiredValidator" runat="server"
                                      ControlToValidate="UserNameTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>
    <tr>
      <td>Password:</td>
      <td><asp:Textbox id="PasswordTextbox" runat="server" TextMode="Password" /></td>
      <td><asp:RequiredFieldValidator id="PasswordRequiredValidator" runat="server"
                                      ControlToValidate="PasswordTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>
    <tr>
      <td>Confirm Password:</td>
      <td><asp:Textbox id="PasswordConfirmTextbox" runat="server" TextMode="Password" /></td>
      <td><asp:RequiredFieldValidator id="PasswordConfirmRequiredValidator" runat="server"
                                      ControlToValidate="PasswordConfirmTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" />
          <asp:CompareValidator id="PasswordConfirmCompareValidator" runat="server"
                                      ControlToValidate="PasswordConfirmTextbox" ForeColor="red"
                                      Display="Static" ControlToCompare="PasswordTextBox"
                                      ErrorMessage="Confirm password must match password." />
      </td>
    </tr>
    <tr>
      <td>Email Address:</td>
      <td><asp:Textbox id="EmailTextbox" runat="server" /></td>
      <td><asp:RequiredFieldValidator id="EmailRequiredValidator" runat="server"
                                      ControlToValidate="EmailTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>


<% if (Membership.RequiresQuestionAndAnswer) { %>

    <tr>
      <td>Password Question:</td>
      <td><asp:Textbox id="PasswordQuestionTextbox" runat="server" /></td>
      <td><asp:RequiredFieldValidator id="PasswordQuestionRequiredValidator" runat="server"
                                      ControlToValidate="PasswordQuestionTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>
    <tr>
      <td>Password Answer:</td>
      <td><asp:Textbox id="PasswordAnswerTextbox" runat="server" /></td>
      <td><asp:RequiredFieldValidator id="PasswordAnswerRequiredValidator" runat="server"
                                      ControlToValidate="PasswordAnswerTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>

<% } %>


    <tr>
      <td></td>
      <td><asp:Button id="CreateUserButton" Text="Create User" OnClick="CreateUser_OnClick" runat="server" /></td>
    </tr>
  </table>
</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 CreateUser_OnClick(sender As Object, args As EventArgs)

  ' Create new user and retrieve create status result.

  Dim status As MembershipCreateStatus
  Dim passwordQuestion As String = ""
  Dim passwordAnswer As String = ""

  If Membership.RequiresQuestionAndAnswer Then
    passwordQuestion = PasswordQuestionTextbox.Text
    passwordAnswer = PasswordAnswerTextbox.Text
  End If

  Try
    Dim newUser As MembershipUser = Membership.CreateUser(UsernameTextbox.Text, PasswordTextbox.Text, _
                                                   EmailTextbox.Text, passwordQuestion, _
                                                   passwordAnswer, True, status)
    If newUser Is Nothing Then
      Msg.Text = GetErrorMessage(status)
    Else
       Response.Redirect("login.aspx")
    End If
  Catch
    Msg.Text = "An exception occurred creating the user."
  End Try

End Sub

Public Function GetErrorMessage(status As MembershipCreateStatus) As String

   Select Case status
   
      Case MembershipCreateStatus.DuplicateUserName:
        Return "Username already exists. Please enter a different user name."

      Case MembershipCreateStatus.DuplicateEmail:
        Return "A username for that email address already exists. Please enter a different email address."

      Case MembershipCreateStatus.InvalidPassword:
        Return "The password provided is invalid. Please enter a valid password value."

      Case MembershipCreateStatus.InvalidEmail:
        Return "The email address provided is invalid. Please check the value and try again."

      Case MembershipCreateStatus.InvalidAnswer:
        Return "The password retrieval answer provided is invalid. Please check the value and try again."

      Case MembershipCreateStatus.InvalidQuestion:
        Return "The password retrieval question provided is invalid. Please check the value and try again."

      Case MembershipCreateStatus.InvalidUserName
        Return "The user name provided is invalid. Please check the value and try again."

      Case MembershipCreateStatus.ProviderError:
        Return "The authentication provider returned an error. Please verify your entry and try again. If the problem persists, please contact your system administrator."

      Case MembershipCreateStatus.UserRejected:
        Return "The user creation request has been canceled. Please verify your entry and try again. If the problem persists, please contact your system administrator."

      Case Else:
        Return "An unknown error occurred. Please verify your entry and try again. If the problem persists, please contact your system administrator."
   End Select

End Function

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>Create User</title>
</head>
<body>

<form id="form1" runat="server">
  <h3>Create New User</h3>
  <asp:Label id="Msg" ForeColor="maroon" runat="server" />
  <table cellpadding="3" border="0">
    <tr>
      <td>Username:</td>
      <td><asp:Textbox id="UsernameTextbox" runat="server" /></td>
      <td><asp:RequiredFieldValidator id="UsernameRequiredValidator" runat="server"
                                      ControlToValidate="UserNameTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>
    <tr>
      <td>Password:</td>
      <td><asp:Textbox id="PasswordTextbox" runat="server" TextMode="Password" /></td>
      <td><asp:RequiredFieldValidator id="PasswordRequiredValidator" runat="server"
                                      ControlToValidate="PasswordTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>
    <tr>
      <td>Confirm Password:</td>
      <td><asp:Textbox id="PasswordConfirmTextbox" runat="server" TextMode="Password" /></td>
      <td><asp:RequiredFieldValidator id="PasswordConfirmRequiredValidator" runat="server"
                                      ControlToValidate="PasswordConfirmTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" />
          <asp:CompareValidator id="PasswordConfirmCompareValidator" runat="server"
                                      ControlToValidate="PasswordConfirmTextbox" ForeColor="red"
                                      Display="Static" ControlToCompare="PasswordTextBox"
                                      ErrorMessage="Confirm password must match password." />
      </td>
    </tr>
    <tr>
      <td>Email Address:</td>
      <td><asp:Textbox id="EmailTextbox" runat="server" /></td>
      <td><asp:RequiredFieldValidator id="EmailRequiredValidator" runat="server"
                                      ControlToValidate="EmailTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>


<% If Membership.RequiresQuestionAndAnswer Then %>

    <tr>
      <td>Password Question:</td>
      <td><asp:Textbox id="PasswordQuestionTextbox" runat="server" /></td>
      <td><asp:RequiredFieldValidator id="PasswordQuestionRequiredValidator" runat="server"
                                      ControlToValidate="PasswordQuestionTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>
    <tr>
      <td>Password Answer:</td>
      <td><asp:Textbox id="PasswordAnswerTextbox" runat="server" /></td>
      <td><asp:RequiredFieldValidator id="PasswordAnswerRequiredValidator" runat="server"
                                      ControlToValidate="PasswordAnswerTextbox" ForeColor="red"
                                      Display="Static" ErrorMessage="Required" /></td>
    </tr>

<% End If %>


    <tr>
      <td></td>
      <td><asp:Button id="CreateUserButton" Text="Create User" OnClick="CreateUser_OnClick" runat="server" /></td>
    </tr>
  </table>
</form>

</body>
</html>

Remarks

Requiring a password question and answer provides an additional layer of security when retrieving or resetting a user's password. Users can supply a question and answer when their user name is created that they can later use to retrieve or reset a forgotten password.

RequiresQuestionAndAnswer is checked when ResetPassword or GetPassword is called. The provider provided with the .NET Framework throws a NotSupportedException if RequiresQuestionAndAnswer is true and the supplied password answer is null.

If EnablePasswordReset and EnablePasswordRetrieval are both false, RequiresQuestionAndAnswer can still be used to enforce the creation of questions and answers when new users are created; however, the question and answer will not be used. You will be able to retrieve the question by using the MembershipUser class.

For more information, see ResetPassword and GetPassword.

Applies to

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