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