This error gets thrown
Bytes to be written to the stream exceed the Content-Length bytes size specified.
when I run the following code:
var request = (HttpWebRequest)WebRequest.Create(url); request.Method = "POST"; request.ContentType = "application/json"; request.ContentLength = Encoding.UTF8.GetByteCount(json); using (var webStream = request.GetRequestStream()) using (var requestWriter = new StreamWriter(webStream, System.Text.Encoding.UTF8)) { requestWriter.Write(json); }
I read, that error could occurs when Method was HEAD or GET, but here it's POST.
Any idea what's wrong there?
The problem is that you're writing the UTF-8 BOM first, because Encoding.UTF8 does that by default. Short but complete example:
using System; using System.IO; using System.Text; class Test { static void Main() { string text = "text"; var encoding = Encoding.UTF8; Console.WriteLine(encoding.GetByteCount(text)); using (var stream = new MemoryStream()) { using (var writer = new StreamWriter(stream, encoding)) { writer.Write(text); } Console.WriteLine(BitConverter.ToString(stream.ToArray())); } } }
Output:
4 EF-BB-BF-74-65-78-74
The simplest fix is either to add the preamble size to the content length, or to use an encoding which doesn't have a BOM:
Encoding utf8NoBom = new UTF8Encoding(false);
Use that instead of Encoding.UTF8, and all should be well.
