JavaScript 判断页面有无特定元素再执行操作

Kevin 杂记 984 次浏览 35条评论

有时去除网页中的一些动态生成元素,如果没法在后端解决,只能使用 JavaScript 解决了。下面贴个简单实现代码,先在页面中检查有无 demo1 选择器元素,如果有则执行删除 demo2 元素。根据需要,还可以加更多判断或进行其它操作。


<p id="demo1">demo1</p>
<p id="demo2">demo2</p>


var pa = document.getElementById("demo1");
if (pa !== null) {
  var pb = document.getElementById("demo2");



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