获取URL中某个参数的值

function getQueryString(name){ ???var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)",‘i‘); ???var res = window.location.search.substr(1).match(reg); ???if(res[2]){ ??????return res[2]; ???}else{ ???????return null; ???}}

var userName = getQueryString(‘userName‘);