public Stream GetRequestStreamAsync(int contentLenght)
{
var result = new MemoryStream();
var writer = new StreamWriter(result);
var b = new char[contentLenght];
_reader.ReadBlockAsync(b, 0, contentLenght);
writer.WriteAsync(b);
writer.FlushAsync();
result.Seek(0, SeekOrigin.Begin);
return(result);
}