使用場景：常用在分享页面 

1、采用正则表达式获取地址栏参数 

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

2、split拆分法 

function getQueryString() {// 获取url中"?"符后的字串const url = location.search; let theRequest = new Object();if (url.indexOf("?") != -1) {let str = url.substr(1);strs = str.split("&");for(let i = 0; i < strs.length; i ++) {theRequest[strs[i].split("=")[0]]=unescape(strs[i].split("=")[1]);}}return theRequest;
}