HTML5 Game - Use Generic EventListener Interface with WebSocket

Description

Use Generic EventListener Interface with WebSocket
Demo

<!DOCTYPE HTML> 
<html> 
  <head> 
    <title>Canvas Demo</title> 
  </head> /*from w ww.  jav  a  2s.c o  m*/
  <body> 
    <h1>Web Sockets Demonstration</h1> 
    <script> 
let chatUrl = 'ws://www.your server.com/chat '; 
let validProtocols = ['chat', 'json']; 
let chatSocket = new WebSocket(chatUrl, validProtocols); 
function CreateWebSocketEventObject() { 
  this.handleError_ = function() { 
    console.log('An error occurred on the chat connection.'); 
  }; 
  this.handleClose_ = function(event) { 
    console.log('The chat connection was closed because ', event.reason); 
  }; 
    
  this.handleOpen_ = function(event) { 
    console.log('The chat connection is open.'); 
  }; 
    
  this.handleMessage_ = function(event) { 
    console.log('A message event has been sent.'); 
    if (chatSocket.protocol === validProtocols[0]) { 
      console.log('The chat protocol is active.'); 
      console.log('The data the server transmitted is: ', event.data); 
    } else { 
      console.log('The json protocol is active.'); 
      console.log('The data the server transmitted is: ', event.data); 
    } 
  }; 
  this.handleEvent = function(event) { 
    switch (event.type) { 
      case 'error': 
        this.handleError_(); 
        break; 
      case 'close': 
        this.handleClose_(event); 
        break; 
      case 'open': 
        this.handleOpen_(event); 
        break; 
      case 'message': 
        this.handleMessage_(event); 
        break; 
      default: 
        console.warn('Unknown event of type ', event.type); 
    } 
  }; 
} 
  
let eventHandlerObject = new CreateWebSocketEventObject(); 
  
chatSocket.addEventListener('error', eventHandlerObject); 
chatSocket.addEventListener('close', eventHandlerObject); 
chatSocket.addEventListener('open', eventHandlerObject); 
chatSocket.addEventListener('message', eventHandlerObject); 
    </script> 
  </body> 
</html>