RoleProvider.IsUserInRole(String, String) 方法

定義

命名空間:

System.Web.Security

組件:

System.Web.ApplicationServices.dll

取得值，指出指定使用者是否在已設定 applicationName 的指定角色中。

public:
 abstract bool IsUserInRole(System::String ^ username, System::String ^ roleName);

public abstract bool IsUserInRole (string username, string roleName);

abstract member IsUserInRole : string * string -> bool

Public MustOverride Function IsUserInRole (username As String, roleName As String) As Boolean

參數

username

String

要搜尋的使用者名稱。

roleName

String

要搜尋的角色。

傳回

Boolean

如果指定的使用者在已設定 applicationName 的指定角色中，則為 true；否則為 false。

範例

下列程式代碼範例示範 方法的範例實作 IsUserInRole 。

public override bool IsUserInRole(string username, string rolename)
{
  if (username == null || username == "")
    throw new ProviderException("User name cannot be empty or null.");
  if (rolename == null || rolename == "")
    throw new ProviderException("Role name cannot be empty or null.");

  bool userIsInRole = false;

  OdbcConnection conn = new OdbcConnection(connectionString);
  OdbcCommand cmd = new OdbcCommand("SELECT COUNT(*) FROM UsersInRoles "  +
                                    " WHERE Username = ? AND Rolename = ? AND ApplicationName = ?", conn);

  cmd.Parameters.Add("@Username", OdbcType.VarChar, 255).Value = username;
  cmd.Parameters.Add("@Rolename", OdbcType.VarChar, 255).Value = rolename;
  cmd.Parameters.Add("@ApplicationName", OdbcType.VarChar, 255).Value = ApplicationName;

  try
  {
    conn.Open();

    int numRecs = (int)cmd.ExecuteScalar();

    if (numRecs > 0)
    {
      userIsInRole = true;
    }
  }
  catch (OdbcException)
  {
    // Handle exception.
  }
  finally
  {
    conn.Close();      
  }

  return userIsInRole;
}

Public Overrides Function IsUserInRole(ByVal username As String, ByVal rolename As String) As Boolean
    If username Is Nothing OrElse username = "" Then _
      Throw New ProviderException("User name cannot be empty or null.")
    If rolename Is Nothing OrElse rolename = "" Then _
      Throw New ProviderException("Role name cannot be empty or null.")

    Dim userIsInRole As Boolean = False

    Dim conn As OdbcConnection = New OdbcConnection(connectionString)
    Dim cmd As OdbcCommand = New OdbcCommand("SELECT COUNT(*) FROM UsersInRoles " & _
                                             " WHERE Username = ? AND Rolename = ? AND ApplicationName = ?", conn)

    cmd.Parameters.Add("@Username", OdbcType.VarChar, 255).Value = username
    cmd.Parameters.Add("@Rolename", OdbcType.VarChar, 255).Value = rolename
    cmd.Parameters.Add("@ApplicationName", OdbcType.VarChar, 255).Value = ApplicationName

    Try
        conn.Open()

        Dim numRecs As Integer = CType(cmd.ExecuteScalar(), Integer)

        If numRecs > 0 Then
            userIsInRole = True
        End If
    Catch e As OdbcException
        ' Handle exception.
    Finally
        conn.Close()
    End Try

    Return userIsInRole
End Function

備註

方法 IsUserInRole 是由 IsUserInRole 類別的 方法呼叫， Roles 以判斷目前的登入使用者是否與所設定 ApplicationName數據源中的角色相關聯。

如果指定的使用者名稱是 null 或是空字串，建議您的提供者擲回例外狀況。

如果指定的角色名稱是 null 或 是空字串，建議您的提供者擲回例外狀況。

另請參閱

• 實作角色提供者