Membership.RequiresQuestionAndAnswer Propriedade

  • Referência

Definição

Namespace:
System.Web.Security
Assembly:
System.Web.dll

Obtém um valor que indica se o provedor de associação padrão exige que o usuário responda uma pergunta de senha para recuperação e redefinição de senha.

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

Valor da propriedade

Boolean

true se uma resposta de senha é necessária para a recuperação e redefinição de senha; caso contrário, false.

Exemplos

O exemplo de código a seguir mostra o elemento de associação na system.web seção do arquivo Web.config para um aplicativo ASP.NET. Ele especifica que o aplicativo usa uma instância do , habilita a SqlMembershipProviderredefinição de senha e requer uma resposta de senha ao executar uma redefinição.

<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>

O exemplo de código a seguir verifica o valor de RequiresQuestionAndAnswer e adiciona os controles necessários para que uma pergunta e resposta de senha sejam fornecidas ao criar um usuário.

Importante

Este exemplo inclui uma caixa de texto que aceita a entrada do usuário, que é uma possível ameaça à segurança. Por padrão, ASP.NET páginas da Web validam que a entrada do usuário não inclui elementos HTML ou script. Para obter mais informações, consulte Visão geral de explorações de 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>

Comentários

Exigir uma pergunta e resposta de senha fornece uma camada adicional de segurança ao recuperar ou redefinir a senha de um usuário. Os usuários podem fornecer uma pergunta e uma resposta quando o nome de usuário é criado que podem ser usados posteriormente para recuperar ou redefinir uma senha esquecida.

RequiresQuestionAndAnswer é verificado quando ResetPassword ou GetPassword é chamado. O provedor fornecido com o .NET Framework lança um NotSupportedException se RequiresQuestionAndAnswer é true e a resposta de senha fornecida é null.

Se EnablePasswordReset e EnablePasswordRetrieval forem ambos false, RequiresQuestionAndAnswer ainda poderá ser usado para impor a criação de perguntas e respostas quando novos usuários forem criados; no entanto, a pergunta e a resposta não serão usadas. Você poderá recuperar a pergunta usando a MembershipUser classe .

Para obter mais informações, consulte ResetPassword e GetPassword.

Aplica-se a

Confira também