获取url里的query参数

function getQueryString(variable) {
        var query = window.location.search.substring(1);
        var vars = query.split("&");
        for (var i = 0; i < vars.length; i++) {
          var pair = vars[i].split("=");
          if (pair[0] == variable) {
            return decodeURIComponent(pair[1]);
          }
        }
        return false;
      }