常用的公用js

1.獲取地址欄某個參數值

//url:地址   params:參數名稱
function getCaption(url,param) {
            var index = url.lastIndexOf('?');
            var url = url.substring(index, a.length);
            var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)");
            var r = url.substr(1).match(reg);
            if (r != null) return unescape(r[2]);
            return null;
        }

如：var a =
      'https://wx.cmfchina.com/WeixinWeb/WeixinWeb_Html/ActivityTemplate/visual.html?activityId=AC20191025WJLCZQ&APP-banner=123&&names=ljks';
console.log(getCaption(a,"activityId"));