从主文档中的 JavaScript 获取 IFrame 的文档
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Get IFrame's document, from JavaScript in main document
提问by user175908
I have this HTML code:
我有这个 HTML 代码：
<html>
<head>
<script type="text/javascript">
function GetDoc(x)
{
return x.document ||
x.contentDocument ||
x.contentWindow.document;
}
function DoStuff()
{
var fr = document.all["myframe"];
while(fr.ariaBusy) { }
var doc = GetDoc(fr);
if (doc == document)
alert("Bad");
else
alert("Good");
}
</script>
</head>
<body>
<iframe id="myframe" src="http://example.com" width="100%" height="100%" onload="DoStuff()"></iframe>
</body>
</html>
The problem is that I get message "Bad". That mean that the document of iframe is not got correctly, and what is actualy returned by GetDoc function is the parent document.
问题是我收到消息“坏”。这意味着iframe的文档没有正确获取，GetDoc函数实际返回的是父文档。
I would be thankful, if you told where I do my mistake. (I want to get document hosted in IFrame.)
如果你告诉我哪里出错了，我将不胜感激。（我想在 IFrame 中托管文档。）
Thank you.
谢谢你。
回答by pkaeding
You should be able to access the document in the IFRAME using the following code:
您应该能够使用以下代码访问 IFRAME 中的文档：
document.getElementById('myframe').contentWindow.document
However, you will not be able to do this if the page in the frame is loaded from a different domain (such as google.com). THis is because of the browser's Same Origin Policy.
但是，如果框架中的页面是从不同的域（例如 google.com）加载的，您将无法执行此操作。这是因为浏览器的同源策略。
回答by Tim Down
The problem is that in IE (which is what I presume you're testing in), the <iframe>element has a documentproperty that refers to the document containing the iframe, and this is getting used before the contentDocumentor contentWindow.documentproperties. What you need is:
问题是在 IE 中（我假设您正在测试的内容），该<iframe>元素具有一个document属性，该属性引用包含 iframe 的文档，并且在contentDocumentorcontentWindow.document属性之前使用了该属性。你需要的是：
function GetDoc(x) {
return x.contentDocument || x.contentWindow.document;
}
Also, document.allis not available in all browsers and is non-standard. Use document.getElementById()instead.
此外，document.all并非在所有浏览器中都可用并且是非标准的。使用document.getElementById()来代替。
回答by Zhanwen Chen
In case you get a cross-domain error:
如果您遇到跨域错误：
If you have control over the content of the iframe - that is, if it is merely loaded in a cross-origin setup such as on Amazon Mechanical Turk - you can circumvent this problem with the <body onload='my_func(my_arg)'>attribute for the inner html.
如果您可以控制 iframe 的内容——也就是说，如果它只是在跨域设置中加载，例如在 Amazon Mechanical Turk 上——您可以使用<body onload='my_func(my_arg)'>内部 html的属性来规避这个问题。
For example, for the inner html, use the thishtml parameter (yes - thisis defined and it refers to the parent window of the inner body element):
例如，对于内部 html，使用thishtml 参数（是的 -this已定义，它指的是内部 body 元素的父窗口）：
<body onload='changeForm(this)'>
<body onload='changeForm(this)'>
In the inner html :
在内部 html 中：
function changeForm(window) {
console.log('inner window loaded: do whatever you want with the inner html');
window.document.getElementById('mturk_form').style.display = 'none';
</script>
