Websockets - 断开服务器消息 [英] Websockets - disconnects on server message
问题描述
我是 Websockets 的新手，正在寻找使用 WS 和 c# 控制台应用程序的工作示例.我遇到了这个，但我已经遇到了问题.当服务器向客户端发送消息时，连接似乎已关闭.我不确定，但我认为握手没问题.这是一个代码:
I'm new to Websockets and looking for working samples using WS and c# console application. I ran into this one, but i already have a problem. It seems that connection is closed when server sends a message to client. I'm not sure but i think handshake is ok. Here is a code:
服务器:
using System;
using System.Net.Sockets;
using System.Net;
using System.Security.Cryptography;
using System.Threading;
namespace ConsoleApplication1
{
class Program
{
static Socket serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
static private string guid = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
static void Main(string[] args)
{
serverSocket.Bind(new IPEndPoint(IPAddress.Any, 8080));
serverSocket.Listen(128);
serverSocket.BeginAccept(null, 0, OnAccept, null);
Console.Read();
}
private static void OnAccept(IAsyncResult result)
{
byte[] buffer = new byte[1024];
try
{
Socket client = null;
string headerResponse = "";
if (serverSocket != null && serverSocket.IsBound)
{
client = serverSocket.EndAccept(result);
var i = client.Receive(buffer);
headerResponse = (System.Text.Encoding.UTF8.GetString(buffer)).Substring(0, i);
// write received data to the console
Console.WriteLine(headerResponse);
Console.WriteLine("=====================");
}
if (client != null)
{
/* Handshaking and managing ClientSocket */
var key = headerResponse.Replace("ey:", "`")
.Split('`')[1] // dGhlIHNhbXBsZSBub25jZQ== \r\n .......
.Replace("\r", "").Split('\n')[0] // dGhlIHNhbXBsZSBub25jZQ==
.Trim();
// key should now equal dGhlIHNhbXBsZSBub25jZQ==
var test1 = AcceptKey(ref key);
var newLine = "\r\n";
var response = "HTTP/1.1 101 Switching Protocols" + newLine
+ "Upgrade: websocket" + newLine
+ "Connection: Upgrade" + newLine
+ "Sec-WebSocket-Accept: " + test1 + newLine + newLine
//+ "Sec-WebSocket-Protocol: chat, superchat" + newLine
//+ "Sec-WebSocket-Version: 13" + newLine
;
// which one should I use? none of them fires the onopen method
client.Send(System.Text.Encoding.UTF8.GetBytes(response));
var i = client.Receive(buffer); // wait for client to send a message
// once the message is received decode it in different formats
Console.WriteLine(Convert.ToBase64String(buffer).Substring(0, i));
Console.WriteLine("=====================");
Console.WriteLine("\n\nPress enter to send data to client");
Console.Read();
var subA = SubArray<byte>(buffer, 0, i);
client.Send(subA);
Console.Read();
Thread.Sleep(10000);//wait for message to be send
}
}
catch (SocketException exception)
{
throw exception;
}
finally
{
if (serverSocket != null && serverSocket.IsBound)
{
serverSocket.BeginAccept(null, 0, OnAccept, null);
}
}
}
public static T[] SubArray<T>(T[] data, int index, int length)
{
T[] result = new T[length];
Array.Copy(data, index, result, 0, length);
return result;
}
private static string AcceptKey(ref string key)
{
string longKey = key + guid;
byte[] hashBytes = ComputeHash(longKey);
return Convert.ToBase64String(hashBytes);
}
static SHA1 sha1 = SHA1CryptoServiceProvider.Create();
private static byte[] ComputeHash(string str)
{
return sha1.ComputeHash(System.Text.Encoding.ASCII.GetBytes(str));
}
}
}
克伦特:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<script type="text/javascript">
function connect() {
var ws = new WebSocket("ws://localhost:8080/service");
ws.onopen = function () {
alert("About to send data");
ws.send("Hello World"); // I WANT TO SEND THIS MESSAGE TO THE SERVER!!!!!!!!
alert("Message sent!");
};
ws.onmessage = function (evt) {
alert("About to receive data");
var received_msg = evt.data;
alert("Message received = "+received_msg);
};
ws.onclose = function () {
// websocket is closed.
alert("Connection is closed...");
};
};
</script>
</head>
<body style="font-size:xx-large" >
<div>
<a href="#" onclick="connect()">Click here to start</a></div>
</body>
</html>
这是来自客户端的连接请求和消息:
Here is a connection request and message from client:
任何帮助将不胜感激.
推荐答案
您不能只是回显"您收到的缓冲区.RFC 说，从客户端到服务器的帧必须被屏蔽.它并不是说从服务器到客户端的消息一定不能，但至少对于 Chrome 来说不应该.因此，如果您想回显数据，您必须解码(取消屏蔽)帧并构建一个新的帧.负载需要与掩码键逐字节异或.
You cannot just "echo" the buffer you received. The RFC says, that frames from client to server must be masked. It doesn't say that messages from server to client must not, but at least for Chrome it shouldn't. Hence, if you want to echo data, you have to decode (unmask) the frame and construct a new one. The payload needs to be XOR'ed byte-by-byte with the mask key.
或者简单地发送这样的数据:
Or simply send data like this:
byte[] send = new byte[3 + 2];
send[0] = 0x81; // last frame, text
send[1] = 3; // not masked, length 3
send[2] = 0x41;
send[3] = 0x42;
send[4] = 0x43;
nwStream.Write(send, 0, send.Length); // nwStream = client.GetStream(), client is a TcpClient
这篇关于Websockets - 断开服务器消息的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
