获取app通过url传过来的参数
转换：
var a = window.location.search
var searchHref = a.replace("?", "");
var params = searchHref.split("&");
var returnParam = {};
params.forEach(function(param) {
var paramSplit = param.split("=");
returnParam[paramSplit[0]] = paramSplit[1];
});
return returnParam