你能在不使用表格的情况下做这个 HTML 布局吗？

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Just float left and right and set to clear both and you're done. No need for tables.

Edit: I know that I got a lot of upvotes for this, and I believed I was right. But there are cases where you simply need to have tables. You can try doing everything with CSS and it will work in modern browsers, but if you wish to support older ones... Not to repeat myself, here the related stack overflow thread and rant on my blog.

Edit2: Since older browsers are not that interesting anymore, I'm using Twitter bootstrap for new projects. It's great for most layout needs and does using CSS.

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Float title left, float button right, and (here's the part I never knew until recently) - make the container of them both {overflow:hidden}.

That should avoid the z-index problem, anyway. If it doesn't work, and you really need the IE5 support, go ahead and use the table.

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Do a double float in a div and use the clearfix. http://www.webtoolkit.info/css-clearfix.html Do you have any padding/margin restrictions?

<div class="clearfix">
<div style="float:left">Title</div>
<input type="button" value="Button" style="float:right" />
</div>

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<div class="group-header">
<input type="button" name="Button" value="Button" style="float:right" />
<span>Title</span>
</div>

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最佳答案

There is nothing wrong with using the tools that are available to you to do the job quickly and correctly.

In this case a table worked perfectly.

I personally would have used a table for this.

I think nested tables should be avoided, things can get messy.

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I would recommend not using a table in this instance, because that is not tabular data; it's purely presentational to have the button located at the far right. This is what I'd do to duplicate your table structure (change to a different H# to suit where you are in your site's hierarchy):

<style>
.group-header { background: yellow; zoom: 1; padding: 8px; }
.group-header:after { content: "."; display: block; height: 0; clear: both; visibility: hidden; }
/* set width appropriately to allow room for button */
.group-header h3 { float: left; width: 300px; }
/* set line-height or margins to align with h3 baseline or middle */
.group-header input { float: right; }
</style>


<div class="group-header">
<h3>This is my title</h3>
<input type="button" value="Collapse"/>
</div>

If you want true vertical alignment in the middle (ie, if the text wraps the button is still middle-aligned with respect to both lines of text), then you either need to do a table or work something with position: absolute and margins. You can add position: relative to your drop-down menu (or more likely its parent) in order to pull it into the same ordering level as the buttons, allowing you to bump it above them with z-index, if it comes to that.

Note that you don't need width: 100% on the div because it's a block-level element, and zoom: 1 makes the div behave like it has a clearfix in IE (other browsers pick up the actual clearfix). You also don't need all those extraneous classes if you're targeting things a bit more specifically, although you might need a wrapper div or span on the button to make positioning easier.

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This is kind of a trick question: it looks terribly simple until you get to

Say I want the title and button to be vertically centered.

I want to state for the record that yes, vertical centring is difficult in CSS. When people post, and it seems endless on SO, "can you do X in CSS" the answer is almost always "yes" and their whinging seems unjustified. In this case, yes, that one particular thing is hard.

Someone should just edit the entire question down to "is vertical centring problematic in CSS?".

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In pure CSS, a working answer will one day be to just use "display:table-cell". Unfortunately that doesn't work across current A-grade browsers, so for all that you might as well use a table if you just want to achieve the same result anyway. At least you'll be sure it works far enough into the past.

Honestly, just use a table if it's easier. It won't hurt.

If the semantics and accessibility of the table element really matter to you, there is a working draft for making your table non-semantic:

http://www.w3.org/TR/wai-aria/#presentation

I think this requires a special DTD beyond XHTML 1.1, which would just stir up the whole text/html vs application/xml debate, so let's not go there.

So, on to your unresolved CSS problem...

To vertically align two elements on their center: it can be done a few different ways, with some obtuse CSS hackery.

If you can fit within the following constraints, then there is a relatively simple way:

The height of the two elements is fixed.
The height of the container is fixed.
The elements will be narrow enough not to overlap (or can be set to a fixed width).

Then you can use absolute positioning with negative margins:

.group-header { height: 50px; position: relative; }
.group-title, .group-buttons { position: absolute; top: 50%; }
# Assuming the height of .group-title is a known 34px
.group-title { left: 0; margin-top: -17px; }
# Assuming the height of .group-buttons is a known 38px
.group-buttons { right: 0; margin-top: -19px; }

But this is pointless in most situations... If you already know the height of the elements, then you can just use floats and add enough margin to position them as needed.

Here is another method which uses the text baseline to vertically align the two columns as inline blocks. The drawback here is that you need to set fixed widths for the columns to fill out the width from the left edge. Because we need to keep the elements locked to a text baseline, we can't just use float:right for the second column. (Instead, we have to make the first column wide enough to push it over.)

<html>
<head>
<title>Layout</title>
<style type="text/css">
.group-header, .group-content { width: 500px; margin: 0 auto; }
.group-header { border: 1px solid red; background: yellow; }
.valign { display: inline-block; vertical-align: middle; }
.group-content { border: 1px solid black; background: #DDD; }
.group-title { padding: 8px; width: 384px; }
.group-buttons { padding: 8px; width: 84px; text-align: right; }
</style>
<!--[if lt IE 8]>
<style type="text/css">
.valign { display: inline; margin-top: -2px; padding-top: 1px; }
</style>
<![endif]-->
</head>
<body>
<div class="group-header">
<div class="valign">
<div class="group-title">This is my title.</div>
</div><!-- avoid whitespace between these! --><div class="valign">
<div class="group-buttons"><input type="button" value="Collapse"></div>
</div>
</div>
<div class="group-content">
<p>And it works perfectly, but mind the hacks.</p>
</div>
</body>
</html>

The HTML: We add .valign wrappers around each column. (Give them a more "semantic" name if it makes you happier.) These need to be kept without whitespace in between or else text spaces will push them apart. (I know it sucks, but that's what you get for being "pure" with the markup and separating it from the presentation layer... Ha!)

The CSS: We use vertical-align:middle to line up the blocks to the text baseline of the group-header element. The different heights of each block will stay vertically centered and push out the height of their container. The widths of the elements need to be calculated to fit the width. Here, they are 400 and 100, minus their horizontal padding.

The IE fixes: Internet Explorer only displays inline-block for natively-inline elements (e.g. span, not div). But, if we give the div hasLayout and then display it inline, it will behave just like inline-block. The margin adjustment is to fix a 1px gap at the top (try adding background colors to the .group-title to see).

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I agree that one should really only use tables for tabular data, for the simple reason that tables don't show until they're finished loading (no matter how fast that is; it's slower that the CSS method). I do, however, feel that this is the simplest and most elegant solution:

<html>
<head>
<title>stack header</title>
<style type="text/css">
#stackheader {
background-color: #666;
color: #FFF;
width: 410px;
height: 50px;
}
#title {
color: #FFF;
float: left;
padding: 15px 0 0 15px;
}
#button {
color: #FFF;
float: right;
padding: 15px 15px 0 0;
}
</style>
</head>


<body>
<div id="stackheader">
<div id="title">Title</div>
<div id="button">Button</div>
</div>
</body>
</html>

The button function and any extra detail can be styled from this basic form. Apologies for the bad tags.

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I've chose to use Flexbox, because it made things so much easier.

You basically need to go to the parent of the children you want to align and add display:box (prefixed of course). To make them sit in the sides, use justify-content. Space between is the right thing when you have elements which need to be aligned to the end, like in this case (see link)...

Then the vertical align issue. Because I made the parent of the two elements, you want to align a Flexbox. It's easy now to use align-items: center.

Then I added the styles you wanted before, removed the float from the title and button in the header and added a padding:

.group-header, .group-content {
width: 500px;
margin: 0 auto;
}
.group-header{
border: 1px solid red;
background: yellow;
overflow: hidden;
display: -webkit-box;
display: -moz-box;
display: box;
display: -webkit-flex;
display: -moz-flex;
display: -ms-flexbox;
display: flex;
-webkit-justify-content: space-between;
-moz-justify-content: space-between;
-ms-justify-content: space-between;
-o-justify-content: space-between;
justify-content: space-between;
webkit-align-items: center;
-moz-align-items: center;
-ms-align-items: center;
-o-align-items: center;
align-items: center;
padding: 8px 0;
}
.group-content{
border: 1px solid black;
background: #DDD;
}
.group-title {
padding-left: 8px;
}
.group-buttons {
padding-right: 8px
}

See Demo