How to center an iframe horizontally?

问题:

Consider the following example: (live demo)

HTML:

<div>div</div>
<iframe></iframe>

CSS:

div, iframe {
    width: 100px;
    height: 50px;
    margin: 0 auto;
    background-color: #777;
}

Result:

Why the iframe is not centrally aligned like the div? How could I centrally align it?

回答1:

Add display:block; to your iframe css.

回答2:

best way and more simple to center an iframe on your webpage is :

<p align="center"><iframe src="http://www.google.com/" width=500 height="500"></iframe></p>

where width and height will be the size of your iframe in your html page.

回答3:

HTML:

<div id="all">
    <div class="sub">div</div>
    <iframe>ss</iframe>
</div>

CSS:

#all{
    width:100%;
    float:left;
    text-align:center;
}
div.sub, iframe {
    width: 100px;
    height: 50px;
    margin: 0 auto;
    background-color: #777;

}

回答4:

If you are putting a video in the iframe and you want your layout to be fluid, you should look at this webpage: Fluid Width Video

Depending on the video source and if you want to have old videos become responsive your tactics will need to change.

If this is your first video, here is a simple solution:

<div class="videoWrapper">
    <!-- Copy & Pasted from YouTube -->
    <iframe width="560" height="349" src="http://www.youtube.com/embed/n_dZNLr2cME?rel=0&hd=1" frameborder="0" allowfullscreen></iframe>
</div>

And add this css:

.videoWrapper {
	position: relative;
	padding-bottom: 56.25%; /* 16:9 */
	padding-top: 25px;
	height: 0;
}
.videoWrapper iframe {
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
}

Disclaimer: none of this is my code, but I've tested it and was happy with the results.

回答5:

The simplest code to align the iframe element:

<div align="center"><iframe width="560" height="315" src="www.youtube.com" frameborder="1px"></iframe></div>

回答6:

You can put iframe inside a <div>

<div>
    <iframe></iframe>
</div>

It works because it is now inside a block element.

回答7:

According to http://www.w3schools.com/css/css_align.asp, setting the left and right margins to auto specifies that they should split the available margin equally. The result is a centered element:

margin-left: auto;margin-right: auto;

回答8:

You can try

<h3 style="text-align:center;"><iframe src=""></iframe></h3>

I hope its useful for you

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