### 返回值:jQuerybefore(content|fn)
### 概述
在每个匹配的元素之前插入内容。
### 参数
#### **content**String, Element, jQuery*V1.0*
插入到每个目标后的内容
#### **function**Function*V1.4*
函数必须返回一个html字符串。
### 示例
#### 描述:
在所有段落之前插入一些HTML标记代码。
##### HTML 代码:
~~~
<p>I would like to say: </p>
~~~
##### jQuery 代码:
~~~
$("p").before("<b>Hello</b>");
~~~
##### 结果:
~~~
[ <b>Hello</b><p>I would like to say: </p> ]
~~~
#### 描述:
在所有段落之前插入一个元素。
##### HTML 代码:
~~~
<p>I would like to say: </p><b id="foo">Hello</b>
~~~
##### jQuery 代码:
~~~
$("p").before( $("#foo")[0] );
~~~
##### 结果:
~~~
<b id="foo">Hello</b><p>I would like to say: </p>
~~~
#### 描述:
在所有段落中前插入一个jQuery对象(类似于一个DOM元素数组)。
##### HTML 代码:
~~~
<p>I would like to say: </p><b>Hello</b>
~~~
##### jQuery 代码:
~~~
$("p").before( $("b") );
~~~
##### 结果:
~~~
<b>Hello</b><p>I would like to say: </p>
~~~
- 速查表
- 核心
- jQuery(selector,[context])
- jQuery(html,[ownerDocument])
- jQuery(callback)
- jQuery.holdReady(hold)
- each(callback)
- size()
- length
- selector
- context
- get([index])
- index([selector|element])
- data([key],[value])
- removeData([name|list])
- jQuery.data(element,[key],[value])
- queue(element,[queueName])
- dequeue([queueName])
- clearQueue([queueName])
- jQuery.noConflict([extreme])
- 选择器
- #id
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- *
- selector1,selector2,selectorN
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- nextAll([expr])
- nextUntil([exp|ele][,fil])
- parent([expr])
- parents([expr])
- parentsUntil([exp|ele][,fil])
- prev([expr])
- prevAll([expr])
- prevUntil([exp|ele][,fil])
- siblings([expr])
- add(expr|ele|html|obj[,con])
- andSelf()
- contents()
- end()
- 文档处理
- append(content|fn)
- appendTo(content)
- prepend(content|fn)
- prependTo(content)
- after(content|fn)
- before(content|fn)
- insertAfter(content)
- insertBefore(content)
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- clone([Even[,deepEven]])
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- hover([over,]out)
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- blur([[data],fn])
- change([[data],fn])
- click([[data],fn])
- dblclick([[data],fn])
- error([[data],fn])
- focus([[data],fn])
- focusout([data],fn)
- keydown([[data],fn])
- keypress([[data],fn])
- keyup([[data],fn])
- mousedown([[data],fn])
- mouseenter([[data],fn])
- mouseleave([[data],fn])
- mousemove([[data],fn])
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- mouseover([[data],fn])
- mouseup([[data],fn])
- resize([[data],fn])
- scroll([[data],fn])
- select([[data],fn])
- submit([[data],fn])
- unload([[data],fn])
- 效果
- show([speed,[easing],[fn]])
- hide([speed,[easing],[fn]])
- slideDown([speed],[easing],[fn])
- slideUp([speed,[easing],[fn]])
- slideToggle([speed],[easing],[fn])
- fadeIn([speed],[easing],[fn])
- fadeOut([speed],[easing],[fn])
- fadeTo([[speed],opacity,[easing],[fn]])
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- delay(duration,[queueName])
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- 工具
- jQuery.support
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- jQuery.each(object,[callback])
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- jQuery.param(obj,[traditional])
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- Deferred
- def.done(donCal,[donCal])
- def.fail(failCal)
- def.isRejected()
- def.isResolved()
- def.reject(args)
- def.rejectWith(context,[args])
- def.resolve(args)
- def.resolveWith(context,args)
- def.then(doneCal,failCal)
- def.progress([type],[target])
- def.pipe([donFil],[faiFil],[proFil])
- def.always(alwCal,[alwCal])
- def.notify(args)
- def.notifyWith(context,[args])
- def.state()
- Callbacks
- callbacks.add(callbacks)
- callbacks.disable()
- callbacks.empty()
- callbacks.fire(arguments)
- callbacks.fired()
- callbacks.fireWith([context][,args])
- callbacks.has(callback)
- callbacks.lock()
- callbacks.locked()
- callbacks.remove(callbacks)
- jQuery.callbacks(flags)
- 关于
- 关于jQuery API 文档
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