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c#tcpclient

TcpClient 505 HTTP Version Not Supported

var client = new TcpClient("www.example.com", 80);
var message = @"GET / HTTP/1.1\r\nHost: www.example.com\r\nConnection: close\r\n\r\n";
var stream = client.GetStream();
var data = Encoding.ASCII.GetBytes(message);
await stream.WriteAsync(data, 0, data.Length);
data = new byte[256];
var bytes = await stream.ReadAsync(data, 0, data.Length);
var responseData = Encoding.ASCII.GetString(data, 0, bytes);

First line of response: HTTP/1.0 505 HTTP Version Not Supported

Note: Using HttpClient/HttpWebRequest is not an option for my use case. It's a long story beyond the scope of this specific question.

Edit: I also tried

var message = @"GET / HTTP/1.0\r\nHost: www.example.com\r\nConnection: close\r\n\r\n";
Solution

  • Compare what you are sending:
    enter image description here

    Against what you want to send:
    enter image description here

    Which boils down to incorrectly assigning message a string literal. You need a regular string instead:

    var message = "GET / HTTP/1.1\r\nHost: www.example.com\r\nConnection: close\r\n\r\n";

    As otherwise, what you send is actually wrong: GET / HTTP/1.1\\r\\nHost: example.com\\r\\nConnection: close\\r\\n\\r\\n