QtWebSocket Sample executing

[fa7eme]

Hi,
I am new to websockets topics and I wanted to run Qt's samples which are in the link below to learn and understand of the way 'QtWebSocket' works:
https://doc.qt.io/qt-5/qtwebsockets-examples.html
but I don't know how to run this example:
https://doc.qt.io/qt-5/qtwebsockets-echoserver-example.html
I made a 'Qwidget' project and another html page like as this example, opened html page and also run my server code but application cannot connect to the server. it says:
ERROR: undefined
DISCONNECTED

[Hanson]

you can see the html content, find somethings like:" var wsUri = "ws://localhost:1234";",
and I think maybe to port(1234) is used,you can change the port and try again.