我想设计一个带有横幅和iframe的网页。我希望iframe可以填充所有剩余的页面高度，并在浏览器调整大小时自动调整大小。是否有可能不编写JavaScript代码，只使用CSS来完成?
我尝试在iframe上设置高度:100%，结果非常接近，但iframe试图填充整个页面高度，包括横幅div元素的30px高度，所以我得到了不必要的垂直滚动条。它并不完美。
我尝试了CSS的margin, padding属性在DIV上成功地占据了网页的整个剩余高度，但这个技巧在iframe上不起作用。
<身体> < div风格= "宽度:100%;高度:30 px;background - color: # cccccc;" > < / div >旗帜 <iframe src="http: //www.google.com.tw" style="width:100%;高度:100%;" > < / iframe > 身体< / >
当前回答
“无缝”属性是一个新的标准，旨在解决这个问题:
http://www.w3schools.com/tags/att_iframe_seamless.asp
当分配此属性时，它将删除边框和滚动条，并将iframe大小设置为其内容大小。 不过它只支持Chrome和最新的Safari浏览器
更多信息请点击这里: HTML5 iFrame无缝属性
其他回答
没错，你所展示的iframe的高度是它的容器(body)的100%。
试试这个:
<body>
<div style="width:100%; height:30px; background-color:#cccccc;">Banner</div>
<div style="width:100%; height:90%; background-color:transparent;">
<iframe src="http: //www.google.com.tw" style="width:100%; height:100%;">
</iframe>
</div>
</body>
当然，将第二个div的高度更改为您想要的高度。
另一种选择是使用vh
<iframe src='/' style="display:block; border:none; height:100vh; width:100%;"></iframe>
2019年更新
现在最好的选择是- flexbox。多年来，所有东西都很好地支持它。去吧，不要回头。下面是一个flexbox的代码示例:
正文，HTML{宽度:100%;高度:100%;保证金:0;填充:0} .row-container{显示:flex;宽度:100%;高度:100%;flex-direction:列;背景颜色:蓝色;溢出:隐藏;} .第一行{background-color:石灰;｝ .第二行{flex-grow: 1;边界:没有;保证金:0;填充:0;｝ < div class = "行容器”> < div class = "板凳”> < / p > < p >一些文本 <p>和一些更多的文本</p> < / div > <iframe src="https://jsfiddle.net/about" class="second-row"></iframe> < / div >
剩下的答案留给学习和历史原因。
关键是要明白这100%是什么。阅读CSS规范可以帮助你。
To make a long story short - there is such a thing as "containing block" - which is not necessary the parent element. Simply said, it is the first element up the hierarchy that has position:relative or position:absolute. Or the body element itself if there is nothing else. So, when you say "width: 100%", it checks the width of the "containing block" and sets the width of your element to the same size. If there was something else there, then you might get contents of a "containing block" that are larger than itself (thus "overflowing").
身高也有同样的作用。只有一个例外。你不能让高度达到浏览器窗口的100%。最顶层的元素是body(或html?)不确定)元素，并且该元素的延伸足以包含其内容。指定高度:100%对它没有影响，因为它没有“父元素”来测量100%。窗口本身不算数。；）
要让某样东西伸展到窗口的100%，你有两个选择:
使用JavaScript
Don't use DOCTYPE. This is not a good practice, but it puts the browsers in "quirks mode", in which you can do height="100%" on elements and it will stretch them to the window size. Do note, that the rest of your page will probably have to be changed too to accommodate for the DOCTYPE changes. Update: I'm not sure if I wasn't wrong already when I posted this, but this certainly is outdated now. Today you can do this in your stylesheet: html, body { height: 100% } and it will actually stretch to the whole of your viewport. Even with a DOCTYPE. min-height: 100% could also be useful, depending on your situation. And I wouldn't advise anyone to make a quirks-mode document anymore either, because it causes way more headaches than solves them. Every browser has a different quirks-mode, so getting your page to look consistently across browsers becomes two orders of magnitude more difficult. Use a DOCTYPE. Always. Preferably the HTML5 one - <!DOCTYPE html>. It's easy to remember and works like a charm in all browsers, even the 10 years old ones. The only exception is when you have to support something like IE5 or something. If you're there, then you're on your own anyway. Those ancient browsers are nothing like the browsers today, and little advice that is given here will help you with them. On the bright side, if you're there, you probably just have to support ONE kind of browser, which gets rid of the compatibility problems. Good luck! Update 2: Hey, it's been a long time! 6 years later, new options are on the scene. I just had a discussion in the comments below, here are more tricks for you that work in today's browsers. Option 1 - absolute positioning. Nice and clean for when you know the precise height of the first part. body, html {width: 100%; height: 100%; margin: 0; padding: 0} .first-row {position: absolute;top: 0; left: 0; right: 0; height: 100px; background-color: lime;} .second-row {position: absolute; top: 100px; left: 0; right: 0; bottom: 0; background-color: red } .second-row iframe {display: block; width: 100%; height: 100%; border: none;} <div class="first-row"> <p>Some text</p> <p>And some more text</p> </div> <div class="second-row"> <iframe src="https://jsfiddle.net/about"></iframe> </div> Some notes - the second-row container is needed because bottom: 0 and right: 0 doesn't work on iframes for some reason. Something to do with in being a "replaced" element. But width: 100% and height: 100% works just fine. display: block is needed because it's an inline element by default and whitespace starts creating weird overflows otherwise. Option 2 - tables. Works when you don't know the height of the first part. You can use either actual <table> tags or do it the fancy way with display: table. I'll go for the latter because it seems to be in fashion these days. body, html {width: 100%; height: 100%; margin: 0; padding: 0} .row-container {display: table; empty-cells: show; border-collapse: collapse; width: 100%; height: 100%;} .first-row {display: table-row; overflow: auto; background-color: lime;} .second-row {display: table-row; height: 100%; background-color: red; overflow: hidden } .second-row iframe {width: 100%; height: 100%; border: none; margin: 0; padding: 0; display: block;} <div class="row-container"> <div class="first-row"> <p>Some text</p> <p>And some more text</p> </div> <div class="second-row"> <iframe src="https://jsfiddle.net/about"></iframe> </div> </div> Some notes - the overflow: auto makes sure that the row always includes all of its contents. Otherwise floating elements can sometimes overflow. The height: 100% on the second row makes sure it expands as much as it can squeezing the first row as small as it gets. Recommended: Option 3 - flexbox - The cleanest one of them all. body, html {width: 100%; height: 100%; margin: 0; padding: 0} .row-container {display: flex; width: 100%; height: 100%; flex-direction: column; background-color: blue; overflow: hidden;} .first-row {background-color: lime; } .second-row { flex-grow: 1; border: none; margin: 0; padding: 0; } <div class="row-container"> <div class="first-row"> <p>Some text</p> <p>And some more text</p> </div> <iframe src="https://jsfiddle.net/about" class="second-row"></iframe> </div> Some notes - the overflow: hidden is because the iframe still generates some sort of overflow even with display: block in this case. It isn't visible in the fullscreen view or the snippet editor, but the small preview window gets an extra scrollbar. No idea what that is, iframes are weird.
“无缝”属性是一个新的标准，旨在解决这个问题:
http://www.w3schools.com/tags/att_iframe_seamless.asp
当分配此属性时，它将删除边框和滚动条，并将iframe大小设置为其内容大小。 不过它只支持Chrome和最新的Safari浏览器
更多信息请点击这里: HTML5 iFrame无缝属性
虽然我同意JS似乎是一个更好的选择，我有一个有点CSS只工作的解决方案。它的缺点是，如果您必须频繁地向iframe html文档添加内容，您将不得不调整一个百分比的时间。
解决方案:
试着不要为你的html文档指定任何高度，
html, body, section, main-div {}
然后只编写如下代码:
#main-div {height:100%;}
#iframe {height:300%;}
注意:div应该是你的主要部分。
这应该是相对有效的。iframe精确地计算可见窗口高度的300%。如果第二个文档的html内容(在iframe中)的高度小于浏览器高度的3倍，它就可以工作。如果你不需要频繁地向文档添加内容，这是一个永久的解决方案，你可以根据你的内容高度找到你自己需要的百分比。
这是因为它可以防止第二个html文档(一个嵌入)从父html文档继承它的高度。它阻止了它，因为我们没有为它们都指定高度。当我们给子对象一个%时，它会寻找它的父对象，如果没有，它会取它的内容高度。前提是其他容器没有给定高度。
