Membership.RequiresQuestionAndAnswer Proprietà
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
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
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 reimpostazione della password e richiede una risposta password durante l'esecuzione di SqlMembershipProvideruna 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 alla password da fornire durante la creazione di un utente.
Importante
Questo esempio include una casella di testo che accetta l'input utente, ovvero una potenziale minaccia di 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 per la password offre un livello di sicurezza aggiuntivo durante il recupero o la reimpostazione della password di un utente. Gli utenti possono fornire una domanda e rispondere quando il nome utente viene creato che possono essere usati in seguito per recuperare o reimpostare una password dimenticata.
RequiresQuestionAndAnswer viene controllato quando ResetPassword o GetPassword viene chiamato. Il provider fornito con .NET Framework genera un 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.