我正在尝试从iframe（cross-origin）中滚动父级。我找到了iframe resizer（David j.Bradshaw）应该能够实现这个目标（我正在使用调整器，因为我还需要iframe根据它的内容调整大小）
我可以使用postMessage但是因为我已经在使用iframe resizer，它有完成我的目标的选项，所以很好地充分利用它。
在父母身上使用：
iFrameResize({
enablePublicMethods : true
});
我应该可以在iframe中调用window.parentIFrame.scrollTo(0,0)。但是，出于某种原因，我无法访问window.parentIFrame。
当我在控制台中记录window时，执行会看到parentIFrame对象，但是当我记录window.parentIFrame时，它会返回undefined。
为什么我无法访问window.parentIFrame对象？
这是我当前的测试情况（从example复制，可以找到here个库：
的index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>iFrame message passing test</title>
<meta name="description" content="iFrame message passing test">
<meta name="viewport" content="width=device-width">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<script type="text/javascript">
//MDN PolyFil for IE8 (This is not needed if you use the jQuery version)
if (!Array.prototype.forEach){
Array.prototype.forEach = function(fun /*, thisArg */){
"use strict";
if (this === void 0 || this === null || typeof fun !== "function") throw new TypeError();
var
t = Object(this),
len = t.length >>> 0,
thisArg = arguments.length >= 2 ? arguments[1] : void 0;
for (var i = 0; i < len; i++)
if (i in t)
fun.call(thisArg, t[i], i, t);
};
}
</script>
</head>
<body>
<h2>Automagically resizing iFrame</h2>
<p>Resize window or click one of the links in the iFrame to watch it resize.</p>
<div style="margin:20px;">
<iframe src="frame.content.html" width="100%" scrolling="no"></iframe>
</div>
<p id="callback">
</p>
<div style="margin: 8px 0;font-size:13px;">
For details on how this works, see
<a href="http://davidjbradshaw.github.io/iframe-resizer/">http://davidjbradshaw.github.io/iframe-resizer/</a>.
</div>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<script type="text/javascript" src="iframeResizer.min.js"></script>
<script type="text/javascript">
iFrameResize({
enablePublicMethods : true
});
</script>
</body>
</html>
frame.content.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>iFrame message passing test</title>
<meta name="description" content="iFrame message passing test">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<style>
*, *:before, *:after {box-model: border-box;}
a { float:right; margin-left:10px;}
</style>
</head>
<body>
<b>iFrame</b>
<a href='#' onclick="$('p:eq(0)').toggle();return false;">Toggle content</a>
<a href='#' onclick="if ('parentIFrame' in window) window.parentIFrame.size(250);return false;">Size(250)</a>
<a id="nested" href="frame.nested.html">Nested</a>
<a href="frame.hover.html">:Hover</a>
<a href="frame.absolute.html">Absolute Position</a>
<a href='#' onclick="if ('parentIFrame' in window) window.parentIFrame.sendMessage('Hello from the iFrame');return false;">Send Message</a>
<a href='#' onclick="if ('parentIFrame' in window) window.parentIFrame.close();return false;">Close</a>
<p>
Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
</p>
<p>
But I must explain to you how all this mistaken idea of denouncing pleasure and praising pain was born and I will give you a complete account of the system, and expound the actual teachings of the great explorer of the truth, the master-builder of human happiness. No one rejects, dislikes, or avoids pleasure itself, because it is pleasure, but because those who do not know how to pursue pleasure rationally encounter consequences that are extremely painful. Nor again is there anyone who loves or pursues or desires to obtain pain of itself, because it is pain, but because occasionally circumstances occur in which toil and pain can procure him some great pleasure. To take a trivial example, which of us ever undertakes laborious physical exercise, except to obtain some advantage from it? But who has any right to find fault with a man who chooses to enjoy a pleasure that has no annoying consequences, or one who avoids a pain that produces no resultant pleasure?
</p>
<p>
On the other hand, we denounce with righteous indignation and dislike men who are so beguiled and demoralized by the charms of pleasure of the moment, so blinded by desire, that they cannot foresee the pain and trouble that are bound to ensue; and equal blame belongs to those who fail in their duty through weakness of will, which is the same as saying through shrinking from toil and pain. These cases are perfectly simple and easy to distinguish. In a free hour, when our power of choice is untrammelled and when nothing prevents our being able to do what we like best, every pleasure is to be welcomed and every pain avoided. But in certain circumstances and owing to the claims of duty or the obligations of business it will frequently occur that pleasures have to be repudiated and annoyances accepted. The wise man therefore always holds in these matters to this principle of selection: he rejects pleasures to secure other greater pleasures, or else he endures pains to avoid worse pains.
</p>
<script>
var level = document.location.search.replace(/\?/,'') || 0;
$('#nested').attr('href','frame.nested.html?'+(++level));
console.log(window); // Does show parentIFrame in the list of properties/objects
console.log(window.parentIFrame); // Returns undefined
</script>
<script type="text/javascript" src="iframeResizer.contentWindow.min.js"></script>
</body>
</html>
答案 0 :(得分：1)
想出来。我不知道为什么，但window.parentIFrame未定义的原因是因为它在页面加载后不能立即使用。
所以这个（使用jQuery）：
$(document).ready(function(){
window.parentIFrame.scrollTo(0,0);
});
没有工作。但是将它绑定到点击或其他东西：
$(document).ready(function(){
$('#test').click(function(){
window.parentIFrame.scrollTo(0,0);
});
});
确实有效。
答案 1 :(得分：0)
实际上，parentIframe在document.ready之后不直接可用。您可能要等待一秒钟或更长时间。因此，您需要将其放入这样的setInterval中：
$(document).ready(function() {
const waitInterval = setInterval(function () {
if (window.parentIFrame) {
parentIFrame.scrollTo(0,0);
clearInterval(waitInterval);
}
}, 100);
})