HTML“pre”标签

定义与用法

The pre element defines preformatted text. The text enclosed in the pre element usually preserves spaces and line breaks. The text renders in a fixed-pitch font.
用pre元素可定义预先格式文字。所有在pre元素内文字的空白间隔以及换行都会被保留。

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在HTML和XHTML中的区别

The "width" attribute of the pre element was deprecated in HTML 4.01.
在HTML4.01中pre元素的"width"属性不被支持。

The "width" attribute of the pre element is not supported in XHTML 1.0 Strict DTD.
XHTML1.0严密型DTD将不再支持pre元素中的”width“属性。

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有关<pre>的注意点

It is worth noting that while <xmp> is deprecated, the <pre> tag does not perform all of the functions of <xmp>:
当<xmp>不被推荐时已经让<pre>不再有什么价值，<pre>不能起到和<xmp>相同的功能：

<pre><b>Hello</b></pre> 会显示为 Hello

<xmp><b>Hello</b></xmp> 则显示为 <b>Hello</b>

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实例

代码	输出结果
<pre> This text is in a fixed-pitch font, and it preserves both      spaces and line breaks </pre>	This text is in a fixed-pitch font, and it preserves both spaces and line breaks

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可选属性

DTD indicates in which DTD the attribute is allowed. S=Strict, T=Transitional, and F=Frameset.
下表中的DTD列指明了被支持的DTD属性。S=Strict（精确的），T=Transitional（传统的），F=Frameset（框架）

属性	值	描述	DTD
width	number	Defines the maximum number of characters per line (usually 40, 80, or 132) 定义pre每行所能接受的最大字符数(一般为40,80或是132)	TF

标准属性

id, class, title, style, dir, lang, xml:lang, xml:space

For a full description, go to Standard Attributes.
查看完整的属性

事件属性

onclick, ondblclick, onmousedown, onmouseup, onmouseover, onmousemove, onmouseout, onkeypress, onkeydown, onkeyup

For a full description, go to Event Attributes.
查看完整的属性

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尝试与演示

Preformatted text
How to control line breaks and spaces with the pre tag.
通过使用pre标签来控制换行与留白空间