从http header中取得签名参数

function TkbmMWCustomSmartService3.ProcessRequest(const Func: string;
  const ClientIdent: TkbmMWClientIdentity;
  const Args: array of Variant): Variant;
var
  helper:TkbmMWHTTPTransportStreamHelper;
  ak:string;
  sign: string;
begin
  Result := '签名错误';
  helper := TkbmMWHTTPTransportStreamHelper(RequestTransportStream.Helper);
  ak := helper.Header.ValueFields['ak'].AsString;
  sign := helper.Header.ValueFields['sign'].AsString;

  exit;
  Result:=inherited ProcessRequest(Func,CLientIdent,Args);
end;