如何使用socket.io请求实现类似jQuery的回调？

Question

What is the best way to implement this pseudocode? For example, when you send an ajax request with JQuery and you can process the received response data in a callback function.

socket.emit(<request data>, function(response_data) { ... });

Answer 1

The typical function callback paradigm isn't necessarily the appropriate way to handle a response from the server when using socket.io. Think of it as two-way communication. A message is sent with an event name and then processed on the server with a corresponding event handler. The server then emits an event back to the client with the response data.

For example:

Client code:

socket.on("ServerSentTime",function(timeData){ //Event Handler For Server Response
   console.log(timeData); 
});


socket.emit("AskServerForTime");     //Event Fired To Server

Server code:

socket.on("AskServerForTime",function() //Event Handler Awaits Client Request
{
   socket.emit("ServerSentTime", new Date().getTime());
});