RoleProvider.GetRolesForUser(String) Method

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()

A string array containing the names of all the roles that the specified user is in for the configured applicationName.

The following code example shows a sample implementation of the GetRolesForUser method.

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 is called by the GetRolesForUser method of the Roles class to retrieve the role names that the specified user is associated with from the data source. Only the roles for the configured ApplicationName are retrieved.

If no roles exist for the specified user for the configured applicationName, we recommend that your provider return a string array with no elements.

If the specified user name is null or is an empty string, we recommend that your provider throw an exception.

• Implementing a Role Provider