ClientRoleProvider.GetRolesForUser(String) Metod

public:
 override cli::array <System::String ^> ^ GetRolesForUser(System::String ^ username);

public override string[] GetRolesForUser(string username);

override this.GetRolesForUser : string -> string[]

Public Overrides Function GetRolesForUser (username As String) As String()

Parametrar

Returer

Rollnamnen som username tillhör eller en tom matris om användaren inte autentiseras.

Undantag

Exempel

Följande exempelkod visar hur du använder den här metoden för att avgöra om användarinloggningen har upphört att gälla innan rollmedlemskapet testas. Den här koden förutsätter att alla giltiga användare är associerade med en eller flera roller. I det här fallet returnerar metoden inte några roller för en tidigare autentiserad GetRolesForUser användare vars inloggning har upphört att gälla. Om användarinloggningen har upphört att gälla visas dialogrutan inloggning i den här koden. Annars anropas IsUserInRole metoden för att avgöra om användaren har rollen "chef". Den begränsade koden finns i en PerformManagerTask metod som inte tillhandahålls.

private void AttemptManagerTask()
{
    System.Security.Principal.IIdentity identity =
        System.Threading.Thread.CurrentPrincipal.Identity;

    // Return if the authentication type is not "ClientForms". 
    // This indicates that the user is logged out.
    if (!identity.AuthenticationType.Equals("ClientForms")) return;

    try
    {
        ClientRoleProvider provider =
            (ClientRoleProvider)System.Web.Security.Roles.Provider;
        String userName = identity.Name;

        // Determine whether the user login has expired by attempting
        // to retrieve roles from the service. Call the ResetCache method
        // to ensure that the roles are retrieved from the service. If no 
        // roles are returned, then the login has expired. This assumes 
        // that every valid user has been assigned to one or more roles.
        provider.ResetCache();
        String[] roles = provider.GetRolesForUser(userName);
        if (roles.Length == 0)
        {
            MessageBox.Show(
                "Your login has expired. Please log in again to access " +
                "the roles service.", "Attempting to access user roles...");

            // Call ValidateUser with empty strings in order to 
            // display the login dialog box configured as a 
            // credentials provider.
            if (!System.Web.Security.Membership.ValidateUser(
                String.Empty, String.Empty))
            {
                MessageBox.Show("Unable to authenticate. " +
                    "Cannot retrieve user roles.", "Not logged in",
                    MessageBoxButtons.OK, MessageBoxIcon.Error);
                return;
            }
        }

        if (provider.IsUserInRole(userName, "manager"))
        {
            PerformManagerTask();
        }
    }
    catch (System.Net.WebException)
    {
        MessageBox.Show(
            "Unable to access the remote service. " +
            "Cannot retrieve user roles.", "Warning",
            MessageBoxButtons.OK, MessageBoxIcon.Warning);
    }
}

Private Sub AttemptManagerTask()

    Dim identity As System.Security.Principal.IIdentity = _
        System.Threading.Thread.CurrentPrincipal.Identity

    ' Return if the authentication type is not "ClientForms". 
    ' This indicates that the user is logged out.
    If Not identity.AuthenticationType.Equals("ClientForms") Then Return

    Try

        Dim provider As ClientRoleProvider = _
            CType(System.Web.Security.Roles.Provider, ClientRoleProvider)
        Dim userName As String = identity.Name

        ' Determine whether the user login has expired by attempting
        ' to retrieve roles from the service. Call the ResetCache method
        ' to ensure that the roles are retrieved from the service. If no 
        ' roles are returned, then the login has expired. This assumes 
        ' that every valid user has been assigned to one or more roles.
        provider.ResetCache()
        Dim roles As String() = provider.GetRolesForUser(userName)
        If roles.Length = 0 Then

            MessageBox.Show( _
                "Your login has expired. Please log in again to access " & _
                "the roles service.", "Attempting to access user roles...")

            ' Call ValidateUser with empty strings in order to 
            ' display the login dialog box configured as a 
            ' credentials provider.
            If Not System.Web.Security.Membership.ValidateUser( _
                String.Empty, String.Empty) Then

                MessageBox.Show("Unable to authenticate. " & _
                    "Cannot retrieve user roles.", "Not logged in", _
                    MessageBoxButtons.OK, MessageBoxIcon.Error)
                Return

            End If

        End If

        If provider.IsUserInRole(userName, "manager") Then
            PerformManagerTask()
        End If

    Catch ex As System.Net.WebException

        MessageBox.Show( _
            "Unable to access the remote service. " & _
            "Cannot retrieve user roles.", "Warning", _
            MessageBoxButtons.OK, MessageBoxIcon.Warning)

    End Try

End Sub

Kommentarer

Metoden GetRolesForUser hämtar rollinformation för den aktuella autentiserade användaren, som du måste ange i parametern username . Du kan hämta användarnamnet via egenskapen enligt staticThread.CurrentPrincipal följande: Thread.CurrentPrincipal.Identity.Name.

Tjänstleverantören cachelagrar rollinformation om det lokala filsystemet för att undvika onödiga tjänstanrop. Mer information finns i klassöversikten ClientRoleProvider .

Se även

• CurrentPrincipal
• IsUserInRole(String, String)
• Klientprogramtjänster
• Så här konfigurerar du klientprogramtjänster