RoleProvider.GetRolesForUser(String) 方法

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

public abstract string[] GetRolesForUser(string username);

abstract member GetRolesForUser : string -> string[]

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

一个字符串数组，其中包含已配置的 applicationName 中指定用户所属的所有角色的名称。

下面的代码示例演示 方法的示例 GetRolesForUser 实现。

public override string[] GetRolesForUser(string username)
{
  if (username == null || username == "")
    throw new ProviderException("User name cannot be empty or null.");

  string tmpRoleNames = "";

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

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

  OdbcDataReader reader = null;

  try
  {
    conn.Open();

    reader = cmd.ExecuteReader();

    while (reader.Read())
    {
      tmpRoleNames += reader.GetString(0) + ",";
    }
  }
  catch (OdbcException)
  {
    // Handle exception.
  }
  finally
  {
    if (reader != null) { reader.Close(); }
    conn.Close();      
  }

  if (tmpRoleNames.Length > 0)
  {
    // Remove trailing comma.
    tmpRoleNames = tmpRoleNames.Substring(0, tmpRoleNames.Length - 1);
    return tmpRoleNames.Split(',');
  }

  return new string[0];
}

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

    Dim tmpRoleNames As String = ""

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

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

    Dim reader As OdbcDataReader = Nothing

    Try
        conn.Open()

        reader = cmd.ExecuteReader()

        Do While reader.Read()
            tmpRoleNames &= reader.GetString(0) & ","
        Loop
    Catch e As OdbcException
        ' Handle exception.
    Finally
        If Not reader Is Nothing Then reader.Close()
        conn.Close()
    End Try

    If tmpRoleNames.Length > 0 Then
        ' Remove trailing comma.
        tmpRoleNames = tmpRoleNames.Substring(0, tmpRoleNames.Length - 1)
        Return tmpRoleNames.Split(CChar(","))
    End If

    Return New String() {}
End Function

GetRolesForUser 由 GetRolesForUser 类的 Roles 方法调用，以从数据源检索与指定用户关联的角色名称。 仅检索已配置 ApplicationName 的角色。

如果所配置的 applicationName的指定用户不存在任何角色，我们建议提供程序返回不带元素的字符串数组。

如果指定的用户名为 null 或为空字符串，建议提供程序引发异常。

• 实现角色提供程序