我從未理解以下代碼是如何等效的:
代碼1:
代碼1:
var app = require("express")();
var server = require('http').Server(app);
var io = require('socket.io').listen(server);
...
io.use(...);
...
server.listen(3000, function(){});
代码 2:
var app = require("express")().listen(3000);
var io = require("socket.io")(app);
...
io.use(...);
代码 3:
var app = express();
var server = http.createServer(app);
var io = require('socket.io').listen(server);
...
io.use(...);
...
server.listen(3000, function(){});
请问您能帮我理解这里发生了什么吗?哪种方法更可取(在什么情况下)?谢谢。