float CSS property places an element on the left or right side of its container, allowing text and inline elements to wrap around it. The element is removed from the normal flow of the page, though still remaining a part of the flow (in contrast to absolute positioning ).

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

A floating element is one where the computed value of float 不是 none .

As float implies the use of the block layout, it modifies the computed value of the display values, in some cases:

指定值 计算值
inline block
inline-block block
inline-table table
table-row block
table-row-group block
table-column block
table-column-group block
table-cell block
table-caption block
table-header-group block
table-footer-group block
inline-flex flex
inline-grid grid
other unchanged
注意: If you're referring to this property from JavaScript as a member of the HTMLElement.style object, modern browsers support float , but in older browsers you have to spell it as cssFloat , with Internet Explorer versions 8 and older using styleFloat . This was an exception to the rule, that the name of the DOM member is the camel-case name of the dash-separated CSS name (due to the fact that "float" is a reserved word in JavaScript, as seen in the need to escape "class" as "className" and escape <label>'s "for" as "htmlFor").

句法

/* Keyword values */
float: left;
float: right;
float: none;
float: inline-start;
float: inline-end;
/* Global values */
float: inherit;
float: initial;
float: unset;
					

float property is specified as a single keyword, chosen from the list of values below.

left

The element must float on the left side of its containing block.

right

The element must float on the right side of its containing block.

none

The element must not float.

inline-start
The element must float on the start side of its containing block. That is the left side with ltr scripts, and the right side with rtl scripts.
inline-end
The element must float on the end side of its containing block. That is the right side with ltr scripts, and the left side with rtl scripts.

形式定义

初始值 none
适用于 all elements, but has no effect if the value of display is none .
继承 no
计算值 如指定
动画类型 discrete

形式句法

left | right | none | inline-start | inline-end
					

范例

How floated elements are positioned

As mentioned above, when an element is floated, it is taken out of the normal flow of the document (though still remaining part of it). It is shifted to the left, or right, until it touches the edge of its containing box, or another floated element .

In this example, there are three colored squares. Two are floated left, and one is floated right. Note that the second "left" square is placed to the right of the first. Additional squares would continue to stack to the right, until they filled the containing box, after which they would wrap to the next line.

A floated element is at least as tall as it's tallest nested floated children. We gave the parent width: 100% and floated it to ensure it is tall enough to encompass it's floated children, and to make sure it takes up the width of the parent so we don't have to clear it's adjacent sibling.

HTML

<section>
  <div class="left">1</div>
  <div class="left">2</div>
  <div class="right">3</div>
  <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit.
     Morbi tristique sapien ac erat tincidunt, sit amet dignissim
     lectus vulputate. Donec id iaculis velit. Aliquam vel
     malesuada erat. Praesent non magna ac massa aliquet tincidunt
     vel in massa. Phasellus feugiat est vel leo finibus congue.</p>
</section>
					

CSS

section {
  border: 1px solid blue;
  width: 100%;
  float: left;
}
div {
  margin: 5px;
  width: 50px;
  height: 150px;
}
.left {
  float: left;
  background: pink;
}
.right {
  float: right;
  background: cyan;
}
					

结果

Clearing floats

Sometimes you may want to force an item to move below any floated elements. For instance, you may want paragraphs to remain adjacent to floats, but force headings to be on their own line. See clear 范例。

规范

规范 状态 注释
CSS Logical Properties and Values Level 1
The definition of 'float and clear' in that specification.
编者草案 Adds the values inline-start and inline-end .
CSS Level 2 (Revision 1)
The definition of 'float' in that specification.
推荐 No change
CSS Level 1
The definition of 'float' in that specification.
推荐 初始定义

浏览器兼容性

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据
Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
float Chrome 完整支持 1 Edge 完整支持 12 Firefox 完整支持 1 IE 完整支持 4 Opera 完整支持 7 Safari 完整支持 1 WebView Android 完整支持 1 Chrome Android 完整支持 18 Firefox Android 完整支持 4 Opera Android 完整支持 10.1 Safari iOS 完整支持 1 Samsung Internet Android 完整支持 1.0
Flow-relative values inline-start and inline-end Chrome 不支持 No Edge 不支持 No Firefox 完整支持 55 IE 不支持 No Opera 不支持 No Safari 不支持 No WebView Android 不支持 No Chrome Android 不支持 No Firefox Android 完整支持 55 Opera Android 不支持 No Safari iOS 不支持 No Samsung Internet Android 不支持 No

图例

完整支持

完整支持

不支持

不支持

另请参阅

元数据

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