ContentLength error for Request Stream in C#

Question

I'm trying to get some data back from rest WS in C# but I'm getting this error:

You must write ContentLength bytes to the request stream before calling [Begin]GetResponse.

This is the code I'm trying to use:

var json = new JavaScriptSerializer().Serialize(order);
        string jsonResponseToString = "";
        HttpWebRequest request =
            (HttpWebRequest)WebRequest.Create("https://myurl.com");
        request.Method = "POST";
        System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
        Byte[] byteArray = encoding.GetBytes(json);
        request.ContentLength = byteArray.Length;
        request.ContentType = @"application/json";
        try
        {                
            using (var response = (HttpWebResponse)request.GetResponse())
            {
                Stream str = response.GetResponseStream();
                var sr = new StreamReader(str, encoding);                    
                
                jsonResponseToString = sr.ReadToEnd();
                var result = new OrderResult();
                result = new JavaScriptSerializer().Deserialize<OrderResult>(jsonResponseToString);
                if (str != null)
                {
                    str.Flush();
                    str.Close();
                }
            }
        }
        catch (WebException ex)
        {
            // 
        }               

The error is happening on this line:

using (var response = (HttpWebResponse)request.GetResponse())

How can I solve this, am I doing something wrong?

Answer 1

As the error is trying to tell you, you need to write your bytes to the request before you can send it.

Call GetRequestStream() and write your bytes.