如题，父页面的JS如何拿到iframe里的dom，并且进行操作？ 原生JS，不用JQ之类的 页面代码：
<body>
<iframe id="container" name="container" src="frames/index.html"></iframe>
</body>
在chrome的console里：
document.getElementById("container")
Blocked a frame with origin "null" from accessing a frame with origin "null". Protocols, domains, and ports must match.
Blocked a frame with origin "null" from accessing a frame with origin "null". Protocols, domains, and ports must match.
Blocked a frame with origin "null" from accessing a frame with origin "null". Protocols, domains, and ports must match.
<iframe id="container" name="container" src="frames/index.html">...</iframe>
document.getElementById("container").contentWindow.document
Blocked a frame with origin "null" from accessing a frame with origin "null". Protocols, domains, and ports must match.
undefined
window.frames["container"].documentBlocked a frame with origin "null" from accessing a frame with origin "null". Protocols, domains, and ports must match.
undefined
![[Web フロントエンド] Node.js クイック スタート](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
虽然是相对路径，还是出现跨域的错误。
最后找到原因了，文件之间的操作是按照跨域处理的，把文件放在web容器里，127.0.0.1 去访问就好了
额 哥们你说清楚一点嘛 ！！！