using System;

using System.IO;

using System.Text;

​

public class Program

{

    public static void Main()

    {

        int? ContentLength = Int32.MaxValue;

        var initialBody = "0123456789";

​

        using (var Body = GenerateStreamFromString(initialBody))

        {

            Console.WriteLine("ContentLength={0} and Body.Length={1}", ContentLength, Body.Length);

            var buffer = new byte[Convert.ToInt32(ContentLength ?? Body.Length)];

            Body.ReadAsync(buffer, 0, buffer.Length);

            var requestBody = Encoding.UTF8.GetString(buffer);

            Console.WriteLine("Result={0}, Length={1}",requestBody, requestBody.Length);

        }

    }

    public static Stream GenerateStreamFromString(string s)

    {

        var stream = new MemoryStream();

        var writer = new StreamWriter(stream);

        writer.Write(s);

        writer.Flush();

        stream.Position = 0;

        return stream;

    }

}