querySelector appendChild原生写法使用 百度Marker使用

typescript 提示 Object is possibly ‘null‘ 的N种解决方法
https://blog.csdn.net/iamlujingtao/article/details/110573421

  //添加闪烁点 只针对一个Marker
        let newSpan = document.createElement('span')
        newSpan.setAttribute('class', 'effectPoint effectPoint1')
        if (newSpan) {
         (document.querySelector('.BMap_Marker') as Element).appendChild(newSpan)
        }