Socket.IO 浏览器兼容代码

if (/Firefox/s/.test(navigator.userAgent)){
    var socket = io.connect('127.0.0.1:8000',{transports:['xhr-polling']}); 
} 
else if (/MSIE (d+.d+);/.test(navigator.userAgent)){
    var socket = io.connect('127.0.0.1:8000',{transports:['jsonp-polling']}); 
} 
else { 
    var socket = io.connect('127.0.0.1:8000'); 
}