如果你正在寻找一个没有jQuery跨起源的解决方案，你可能想看看我的想法:

<main id="container"></main>
<script>
  fetch('https://example.com').then(response => {
    return response.text();
  }).then(data => {
    const iframeContainer = window.document.getElementById('container');
    const iframe = document.createElement('iframe');
    iframe.frameBorder = 'none';
    iframe.width = '100%';
    iframe.addEventListener("load", function() {
      iframe.height = iframe.contentWindow.document.body.scrollHeight;
    })
    const finalHtml = data;
    const blob = new Blob([finalHtml], {type: 'text/html'});
    iframe.src = window.URL.createObjectURL(blob);
    iframeContainer.appendChild(iframe);
  })
</script>

下面是一个跨浏览器的解决方案，如果你不想使用jQuery:

/**
 * Resizes the given iFrame width so it fits its content
 * @param e The iframe to resize
 */
function resizeIframeWidth(e){
    // Set width of iframe according to its content
    if (e.Document && e.Document.body.scrollWidth) //ie5+ syntax
        e.width = e.contentWindow.document.body.scrollWidth;
    else if (e.contentDocument && e.contentDocument.body.scrollWidth) //ns6+ & opera syntax
        e.width = e.contentDocument.body.scrollWidth + 35;
    else (e.contentDocument && e.contentDocument.body.offsetWidth) //standards compliant syntax – ie8
        e.width = e.contentDocument.body.offsetWidth + 35;
}

在我试遍了世界上所有的方法之后，这个方法真的很适合我。

index . html

<style type="text/css">
html, body{
  width:100%;
  height:100%;
  overflow:hidden;
  margin:0px;   
}
</style>
<script type="text/javascript" src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
<script type="text/javascript">
function autoResize(iframe) {
    $(iframe).height($(iframe).contents().find('html').height());
}
</script>

<iframe src="http://iframe.domain.com" width="100%" height="100%" marginheight="0" frameborder="0" border="0" scrolling="auto" onload="autoResize(this);"></iframe>

如果你可以控制IFRAME内容和父窗口，那么你需要IFRAME调整器。

这个库允许自动调整相同域和跨域iframe的高度和宽度，以适应它们所包含的内容。它提供了一系列功能来解决使用iFrames时最常见的问题，包括:

Height and width resizing of the iFrame to content size. Works with multiple and nested iFrames. Domain authentication for cross domain iFrames. Provides a range of page size calculation methods to support complex CSS layouts. Detects changes to the DOM that can cause the page to resize using MutationObserver. Detects events that can cause the page to resize (Window Resize, CSS Animation and Transition, Orientation Change and Mouse events). Simplified messaging between iFrame and host page via postMessage. Fixes in page links in iFrame and supports links between the iFrame and parent page. Provides custom sizing and scrolling methods. Exposes parent position and viewport size to the iFrame. Works with ViewerJS to support PDF and ODF documents. Fallback support down to IE8.

我发现这个调整器工作得更好:

function resizer(id)
{

    var doc = document.getElementById(id).contentWindow.document;
    var body_ = doc.body;
    var html_ = doc.documentElement;

    var height = Math.max( body_.scrollHeight, body_.offsetHeight, html_.clientHeight,     html_.scrollHeight, html_.offsetHeight );
    var width  = Math.max( body_.scrollWidth, body_.offsetWidth, html_.clientWidth, html_.scrollWidth, html_.offsetWidth );

    document.getElementById(id).height = height;
    document.getElementById(id).width = width;

}

注意，样式对象被删除了。

我知道这个帖子很旧了，但我相信这是另一种方式。我在我的代码中实现了。完美的工作在页面加载和页面大小调整:

var videoHeight;
var videoWidth;
var iframeHeight;
var iframeWidth;

function resizeIframe(){
    videoHeight = $('.video-container').height();//iframe parent div's height
    videoWidth = $('.video-container').width();//iframe parent div's width

    iframeHeight = $('.youtubeFrames').height(videoHeight);//iframe's height
    iframeWidth = $('.youtubeFrames').width(videoWidth);//iframe's width
}
resizeIframe();


$(window).on('resize', function(){
    resizeIframe();
});