html - 与 'ws://localhost:52312/' 的 WebSocket 连接失败 : Error during WebSocket handshake: Unexpected response code: 200

Question

我正在尝试实现一个简单的 HTML5 WebSocket，但连接根本没有建立，并且在创建 WebSocket 对象时出现以下错误

WebSocket connection to 'ws://localhost:52312/' failed: Error during WebSocket handshake: Unexpected response code: 200

下面是代码

 document.addEventListener("DOMContentLoaded", function (event) {
        function runHub() {
            if ("WebSocket" in window) {

                console.log('WebSocket is supported by your browser.');

                //var serviceUrl = 'ws://localhost:52312/';
                var serviceUrl = 'ws://localhost:52312/home/GetNotificationCount';

                var protocol = 'Chat-1.0';
                var socket = new WebSocket(serviceUrl);

                socket.onopen = function () {
                    console.log('Connection Established!');
                };

                socket.onclose = function (error) {
                    console.log('Connection Closed!');
                    console.log('Error Occured: ' + JSON.stringify(error));
                };

                socket.onerror = function (error) {
                    console.log('Error Occured: ' + JSON.stringify(error));
                };

                socket.onmessage = function (e) {
                    if (typeof e.data === "string") {
                        console.log('String message received: ' + e.data);
                    }
                    else if (e.data instanceof ArrayBuffer) {
                        console.log('ArrayBuffer received: ' + e.data);
                    }
                    else if (e.data instanceof Blob) {
                        console.log('Blob received: ' + e.data);
                    }
                };


                if (!socket.readyState === WebSocket.CLOSED) {
                    socket.send($('#notificationCount').text);
                    //socket.close();

                }

            }
        }

        var run = setInterval(function () {
            runHub();
        }, 10000)
    });

有人对此有任何想法吗？

Answer 1

根据https://www.rfc-editor.org/rfc/rfc6455#section-4.1

Once the client's opening handshake has been sent, the client MUST wait for a response from the server before sending any further data. The client MUST validate the server's response as follows:

1. If the status code received from the server is not 101, the client handles the response per HTTP [RFC2616] procedures. In particular, the client might perform authentication if it receives a 401 status code; the server might redirect the client using a 3xx status code (but clients are not required to follow them), etc. Otherwise, proceed as follows.

第 4.2.2 节详细说明:除了使用代码 101 和适当的 header 进行响应之外，服务器可能会要求身份验证(响应代码 401)，可能会重定向(3xx 代码)，并且如果您尝试建立安全连接，则应该执行 TLS 握手(如果您使用 wss:// 协议(protocol))。

位于 localhost:52312 的服务器响应代码 200 - websocket 标准，如您在上面看到的，在此响应中没有定义任何意义。因此，客户有权利提出异常(exception)。问题出在服务器上。