如何在body标签中插入insertBefore()元素?

如何在body标签中插入insertBefore()元素?

问题描述:

我正在这样尝试在js中使用insertBefore:

I am trying to use insertBefore in js like this:

var p = document.createElement("p");
p.innerHTML = "test1";
document.body.insertBefore(p, null);

var p = document.createElement("p");
p.innerHTML = "test2";
document.body.insertBefore(p, null);

但这会在body标签关闭之前添加最后一个p元素,我该如何使用它是否会在打开时添加到顶部?所以最后添加的元素将是body标签中的第一个元素。

But that would add the last p element just before the close of the body tag, how could I use it so it will be added to the top when it opens? So the last element added will be the first element inside the body tag.

我尝试过:

document.body.insertBefore(p, document.getElementsByTagName('body')[0]);

但是萤火虫显示:

未找到节点代码: 8

您可以获取 body 元素和 firstChild 属性。然后将其用作参考。

You can get the first child of the body element with the firstChild property. Then use it as the reference.

const p = document.createElement("p");
p.textContent = "test1";
document.body.insertBefore(p, document.body.firstChild);

出于某些原因,我对代码进行了现代化处理:)

I modernized your code for reasons :)