jquery之wrap(),wrap(),unwrap()方法詳解

wrap()：為每個符合元素外新增指定的HTML結構，

wrapAll(): 為所有符合元素（作為一個整體）外層新增一個指定的HTML結構wrap( )函數用於在每個符合元素外部包裹指定的HTML結構。

與該函數相對的是unwrap()函數，用於當前匹配元素的父元素(只移除父元素，其內部節點全部保留)。

該函數屬於<a href="http://www.php.cn/wiki/1495.html" target="_blank">jQuery</a>物件(實例)。

語法

jQueryObject.wrap( wrapper )

參數

#參數	描述
wrapper	String/Element/jQuery/Function類型用於包裹匹配元素的節點。

如果參數wrapper為字串，則將其視為jQuery選擇器或html字串，jQuery會自行判斷。

jQuery 1.4 新增支援：參數wrapper可以為函數。 wrap()將根據匹配的所有元素遍歷執行該函數，函數中的this#將指向對應的DOM元素。

wrap()也會為函數傳入一個參數，也就是目前元素在符合元素中的索引。 函數的回傳值就是用於包裹的節點內容(可以是html字串、DOM元素或jQuery物件)。

注意：如果wrapper匹配多個元素，則只將第一個元素作為包裹元素。

注意：如果wrapper是多層嵌套的元素(例如)，wrap()將從外往內檢查每層嵌套的第一個節點。如果該節點沒有子節點或第一個子節點不是Element節點(例如文字節點、註解節點等)，就停止向內查找，直接在目前節點內部的末端位置追加(append() )當前匹配元素。

傳回值

wrap()函數的回傳值為jQuery類型，返回目前jQuery對象本身(以便於進行鍊式風格的程式設計)。

注意：即使wrapper元素是目前頁面中的元素，該元素也不會從原始位置上消失。因為wrap()使用的是該元素的副本(克隆)來充當包裹。

範例&說明

wrap()函數用於在每個符合元素之前的位置插入內容：

<span class="tag"><p><span class="pln">段落文本1<span class="tag"><span></span></p><span class="pln"><br/><span class="tag"><p><span class="pln">段落文本2<span class="tag"><span></span></p><span class="pln"><br/><br/><span class="tag"><script<span class="pln"> <span class="atn">type<span class="pun">=<span class="atv">"text/<a href="http://www.php.cn/wiki/48.html" target="_blank">javascript</a>"<span class="tag">><span class="pln"><br/>$<span class="pun">(<span class="str">"p"<span class="pun">).<span class="pln">wrap<span class="pun">(<span class="pln"> <span class="str">&#39;<p></p>&#39;<span class="pln"> <span class="pun">);<span class="pln"> <br/><span class="tag"></script><span class="pln"><br/><br/><span class="com"><!--以下是jQuery代码执行后的html内容--><span class="pln"><br/><span class="tag"><p><p><span class="pln">段落文本1<span class="tag"><span></span></p></p><span class="pln"><br/><span class="tag"><p><p><span class="pln">段落文本2<span class="tag"><span></span></p></p></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>

以下面這段HTML程式碼為例：

<span class="tag"><p<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n1"<span class="tag">><span class="pln"><br/>    <span class="tag"><span<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n2"<span class="tag">><span class="pln">span#n2<span class="tag"></span><span class="pln">    <br/><span class="tag"></p><span class="pln"><br/><span class="tag"><p<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n3"<span class="tag">><span class="pln"><br/>    <span class="tag"><input<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n4"<span class="pln"> <span class="atn">type<span class="pun">=<span class="atv">"text"<span class="pln"> <span class="tag">/><span class="pln"><br/><span class="tag"></p><span class="pln"><br/><span class="tag"><span<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n5"<span class="tag">><span class="pln">多层嵌套1<span class="tag"></span><span class="pln"><br/><span class="tag"><span<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n6"<span class="tag">><span class="pln">多层嵌套2<span class="tag"></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>

以下jQuery範例程式碼用於示範wrap()函數的具體用法：

<span class="com">// 在n2元素外包裹strong元素：<strong>{#n2}</strong><span class="pln"><br/>$<span class="pun">(<span class="str">"#n2"<span class="pun">).<span class="pln">wrap<span class="pun">(<span class="str">&#39;<strong/>&#39;<span class="pun">);<span class="pln"><br/><br/><br/><span class="com">// 在n4元素外包裹form元素：<form name="myForm">{#n4}</form><span class="pln"><br/>$<span class="pun">(<span class="str">"#n4"<span class="pun">).<span class="pln">wrap<span class="pun">(<span class="str">&#39;<form name="myForm"></form>&#39;<span class="pun">);<span class="pln"><br/><br/><br/><span class="com">// 在每个p元素外包裹p元素：<p data_id="index">{p}</p><span class="pln"><br/>$<span class="pun">(<span class="str">"p"<span class="pun">).<span class="pln">wrap<span class="pun">(<span class="pln"> <span class="kwd">function<span class="pun">(<span class="pln">index<span class="pun">){<span class="pln"><br/>    <span class="kwd"><a href="http://www.php.cn/wiki/135.html" target="_blank">return</a><span class="pln"> <span class="str">&#39;<p data_id="&#39;<span class="pln"> <span class="pun">+<span class="pln"> index <span class="pun">+<span class="pln"> <span class="str">&#39;"></p>&#39;<span class="pun">;<span class="pln">   <br/><span class="pun">}<span class="pln"> <span class="pun">);<span class="pln"><br/><br/><br/><span class="com">// 在n5元素外包裹嵌套的p元素：<p><p><em><b>{#n5}</b></em></p></p><span class="pln"><br/>$<span class="pun">(<span class="str">"#n5"<span class="pun">).<span class="pln">wrap<span class="pun">(<span class="pln"> <span class="str">&#39;<p><p><em><b></b></em></p></p>&#39;<span class="pln"> <span class="pun">);<span class="pln"><br/><br/><br/><span class="com">// 在n6元素外包裹嵌套的p元素：<p><p> <em><b></b></em>${#n5}</p></p><span class="pln"><br/><span class="com">// wrap()会从外层p依次往内部查找，以确定n5元素的所在位置<span class="pln"><br/><span class="com">// wrap()将从外往内检查每层嵌套的第一个元素，如果该元素没有子元素或者第一个子元素不是Element节点，就停止向内查找<span class="pln"><br/><span class="com">// 由于参数的&#39;<p>&#39;后面有空格(文本节点)，也就是说p元素的第一个子元素不是Element类型，因此直接将n6插入到p元素内部的末尾位置<span class="pln"><br/>$<span class="pun">(<span class="str">"#n6"<span class="pun">).<span class="pln">wrap<span class="pun">(<span class="pln"> <span class="str">&#39;<p><p> <em><b></b></em></p></p>&#39;<span class="pln"> <span class="pun">);</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>

運行程式碼

wrap()會將包裹元素的開始標記和結束標記分別置於匹配元素的兩側，不會額外添加任何空白字元 ，上述程式碼執行後的完整html程式碼如下(格式未作任何調整)：

<span class="tag"><p<span class="pln"> <span class="atn">data_id<span class="pun">=<span class="atv">"0"<span class="tag">><p<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n1"<span class="tag">><span class="pln"><br/>    <span class="tag"><strong><span<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n2"<span class="tag">><span class="pln">span#n2<span class="tag"></span></strong><span class="pln">    <br/><span class="tag"></p></p><span class="pln"><br/><span class="tag"><p<span class="pln"> <span class="atn">data_id<span class="pun">=<span class="atv">"1"<span class="tag">><p<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n3"<span class="tag">><span class="pln"><br/>    <span class="tag"><form<span class="pln"> <span class="atn">name<span class="pun">=<span class="atv">"myForm"<span class="tag">><input<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n4"<span class="pln"> <span class="atn">type<span class="pun">=<span class="atv">"text"<span class="tag">></form><span class="pln"><br/><span class="tag"></p></p><span class="pln"><br/><span class="tag"><p><p><em><b><span<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n5"<span class="tag">><span class="pln">多层嵌套1<span class="tag"></span></b></em></p></p><span class="pln"><br/><span class="tag"><p><p><span class="pln"> <span class="tag"><em><b></b></em><span<span class="pln"> <span class="atn">id<span class="pun">=<span class="atv">"n6"<span class="tag">><span class="pln">多层嵌套2<span class="tag"></span></p></p></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>

以上是jquery之wrap(),wrap(),unwrap()方法詳解的詳細內容。更多資訊請關注PHP中文網其他相關文章！