can't conduct the same code in visual studio 2019

potBagMeat

Hi, everybody.
Here is the thing.
Recently, I have been developing a simple application that can transfer data from c++ to javascript files. So I found a way using websocket. I check the example code in QT, which is standalone example that creates a dialog between html and an qt app. thus, I am using the same method to transfer data. However, I found the same code, which can be conducted successfully on qt creator, can't perform correctly on visual studio 2019. The code I use is :

#include "QtGuiApplication1.h"


#include <QtWidgets/QApplication>


int main(int argc, char** argv)
{
    QApplication app(argc, argv);

    
    QWebSocketServer server(QStringLiteral("QWebChannel Standalone Example Server"), QWebSocketServer::NonSecureMode);
    if (!server.listen(QHostAddress::LocalHost, 12445)) {
        qFatal("Failed to open web socket server.");
        return 1;
    }

 
    WebSocketClientWrapper clientWrapper(&server);



    QWebChannel webChannel;
    QObject::connect(&clientWrapper, &WebSocketClientWrapper::clientConnected,
        &webChannel, &QWebChannel::connectTo);

    return app.exec();
}

and the html code is

<!DOCTYPE html>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
        <script type="text/javascript" src="./qwebchannel.js"></script>
        <script type="text/javascript">
            //BEGIN SETUP
            function output(message) {
                var output = document.getElementById("output");
                output.innerHTML = output.innerHTML + message + "\n";
            }
            window.onload = function() {
                if (location.search != "")
                    var baseUrl = (/[?&]webChannelBaseUrl=([A-Za-z0-9\-:/\.]+)/.exec(location.search)[1]);
                else
                    var baseUrl = "ws://localhost:12445";

                output("Connecting to WebSocket server at " + baseUrl + ".");
                var socket = new WebSocket(baseUrl);

                socket.onclose = function() {
                    console.error("web channel closed");
                };
                socket.onerror = function(error) {
                    console.error("web channel error: " + error);
                };
                socket.onopen = function() {
                    output("WebSocket connected, setting up QWebChannel.");
                    new QWebChannel(socket, function(channel) {
                        // make core object accessible globally
                        var webobj = channel.objects.webobj;
                        //var webobj = channel.objects.webobj;
                        //window.webobj = channel.objects.webobj;
                        console.log(webobj);
                        console.log(webobj.jsonData.y);
                        x.innerHTML = "x:" + "3";
                        webobj.dataChanged.connect(function (arg) {
                                       x.innerHTML = "x:" + "3";
                                       y.innerHTML = "y:" + arg.y.toFixed(4);
                                       console.log("1111");
                                   });
                        //console.log(channel.objects);
                        document.getElementById("send").onclick = function() {
                            var input = document.getElementById("input");
                            var text = input.value;
                            if (!text) {
                                return;
                            }

                            output("Sent message: " + text);
                            input.value = "";
                //            core.receiveText(text);
                        }
                  //      console.log(core.sendText);
                    //    core.sendText.connect(function(message) {
                     //       output("Received message: " + message);
                       // }
                     //   );

                       // core.receiveText("Client connected, ready to send/receive messages!");
                        output("Connected to WebChannel, ready to send/receive messages!");
                    });
                }
            }
            //END SETUP
        </script>
        <style type="text/css">
            html {
                height: 100%;
                width: 100%;
            }
            #input {
                width: 400px;
                margin: 0 10px 0 0;
            }
            #send {
                width: 90px;
                margin: 0;
            }
            #output {
                width: 500px;
                height: 300px;
            }
        </style>
        <p id="x">x:</p>
        <p id="y">y:</p>
    </head>
    <body>
        <textarea id="output"></textarea><br />
        <input id="input" /><input type="submit" id="send" value="Send" onclick="javascript:click();" />
    </body>
</html>

when I run the code on qt creator, I found the html could trigger the socket.onopen signals. However, when I run the same code on visual studio 2019, I found that the socket.onopen signals were never triggered.
I wonder there will be any thoughts can help me.
Thanks in advance!