Membership.RequiresQuestionAndAnswer Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System.Web.Security
Assembly:
System.Web.dll

Ottiene un valore che indica se il provider di appartenenze predefinito richiede agli utenti di rispondere a una domanda per la password prima di consentire la reimpostazione e il recupero della password.

public:
 static property bool RequiresQuestionAndAnswer { bool get(); };
public static bool RequiresQuestionAndAnswer { get; }
static member RequiresQuestionAndAnswer : bool
Public Shared ReadOnly Property RequiresQuestionAndAnswer As Boolean

Valore della proprietà

Boolean

true se è necessaria una risposta per la reimpostazione e il recupero della password. In caso contrario, false.

Esempio

Nell'esempio di codice seguente viene illustrato l'elemento di appartenenza nella system.web sezione del file Web.config per un'applicazione ASP.NET. Specifica che l'applicazione usa un'istanza di , abilita la SqlMembershipProviderreimpostazione della password e richiede una risposta alla password durante l'esecuzione di una reimpostazione.

<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>

L'esempio di codice seguente controlla il valore di RequiresQuestionAndAnswer e aggiunge i controlli necessari per una domanda e una risposta per la password da fornire durante la creazione di un utente.

Importante

Questo esempio include una casella di testo che accetta l'input dell'utente, che rappresenta una potenziale minaccia per la sicurezza. Per impostazione predefinita, le pagine Web ASP.NET verificano che l'input dell'utente non includa script o elementi HTML. Per altre informazioni, vedere Cenni preliminari sugli attacchi tramite script.

<%@ 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>

Commenti

La richiesta di una domanda e una risposta alla password offrono un ulteriore livello di sicurezza durante il recupero o la reimpostazione della password di un utente. Gli utenti possono fornire una domanda e rispondere quando viene creato il nome utente che possono usare in un secondo momento per recuperare o reimpostare una password dimenticata.

RequiresQuestionAndAnswer viene controllato quando ResetPassword viene chiamato o GetPassword . Il provider fornito con .NET Framework genera un'eccezione NotSupportedException if RequiresQuestionAndAnswertrue e la risposta della password fornita è null.

Se EnablePasswordReset e EnablePasswordRetrieval sono entrambi false, RequiresQuestionAndAnswer possono comunque essere usati per applicare la creazione di domande e risposte quando vengono creati nuovi utenti. Tuttavia, la domanda e la risposta non verranno usate. Sarà possibile recuperare la domanda usando la MembershipUser classe .

Per altre informazioni, vedere ResetPassword e GetPassword.

Si applica a

Vedi anche