uTools-Manuals/docs/php/array.html
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title>新建一个数组</title>
</head>
<body class="docs"><div id="layout">
<div id="layout-content"><div id="function.array" class="refentry">
<div class="refnamediv">
<h1 class="refname">array</h1>
<p class="verinfo">(PHP 4, PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">array</span> &mdash; <span class="dc-title">
新建一个数组
</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.array-description">
<h3 class="title">说明</h3>
<div class="methodsynopsis dc-description">
<span class="methodname"><strong>array</strong></span>
([ <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$...</code></span>
] ) : <span class="type">array</span></div>
<p class="para rdfs-comment">
创建一个数组。关于数组是什么的信息请阅读<a href="language.types.array.html" class="link">数组</a>一节。
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.array-parameters">
<h3 class="title">参数</h3>
<p class="para">
<dl>
<dt>
<code class="parameter">...</code></dt>
<dd>
<p class="para">
语法“index =&gt; values”用逗号分开定义了索引和值。索引可以是字符串或数字。如果省略了索引会自动产生从
0 开始的整数索引。如果索引是整数,则下一个产生的索引将是目前最大的整数索引
+ 1。注意如果定义了两个完全一样的索引则后面一个会覆盖前一个。
</p>
<p class="para">
在最后一个定义的数组项目之后加一个逗号虽然不常见,却是合法的语法。
</p>
</dd>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.array-returnvalues">
<h3 class="title">返回值</h3>
<p class="para">
返回根据参数建立的数组。参数可以用 <em>=&gt;</em>
运算符给出索引。关于数组是什么的信息请阅读<a href="language.types.array.html" class="link">数组</a>一节。
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.array-examples">
<h3 class="title">范例</h3>
<p class="para">
下面的例子演示了怎样建立一个二维数组,怎样给相应的数组指定键名,以及怎样在普通数组中略过和继续数字索引。
<div class="example" id="example-6083">
<p><strong>Example #1 <span class="function"><strong>array()</strong></span> 例子</strong></p>
<div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$fruits&nbsp;</span><span style="color: #007700">=&nbsp;array&nbsp;(<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #DD0000">"fruits"&nbsp;&nbsp;</span><span style="color: #007700">=&gt;&nbsp;array(</span><span style="color: #DD0000">"a"&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #DD0000">"orange"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"b"&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #DD0000">"banana"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"c"&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #DD0000">"apple"</span><span style="color: #007700">),<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #DD0000">"numbers"&nbsp;</span><span style="color: #007700">=&gt;&nbsp;array(</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">2</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">3</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">4</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">5</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">6</span><span style="color: #007700">),<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #DD0000">"holes"&nbsp;&nbsp;&nbsp;</span><span style="color: #007700">=&gt;&nbsp;array(</span><span style="color: #DD0000">"first"</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">5&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #DD0000">"second"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"third"</span><span style="color: #007700">)<br />);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
</div>
</div>
</p>
<p class="para">
<div class="example" id="example-6084">
<p><strong>Example #2 <span class="function"><strong>array()</strong></span> 的自动索引</strong></p>
<div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$array&nbsp;</span><span style="color: #007700">=&nbsp;array(</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">8&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;&nbsp;</span><span style="color: #0000BB">4&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">19</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">3&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">13</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">print_r</span><span style="color: #007700">(</span><span style="color: #0000BB">$array</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
</div>
<div class="example-contents"><p>以上例程会输出:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
Array
(
[0] =&gt; 1
[1] =&gt; 1
[2] =&gt; 1
[3] =&gt; 13
[4] =&gt; 1
[8] =&gt; 1
[9] =&gt; 19
)
</pre></div>
</div>
</div>
</p>
<p class="para">
注意索引 3 被定义了两次,保留了最后的值 13。索引 4 在 索引
8 之后定义,下一个自动生成的索引(值为 19 那个)为 9因为最大的索引是 8。
</p>
<p class="para">
本例建立了从 1 开始的数组。
<div class="example" id="example-6085">
<p><strong>Example #3 从 1 开始索引的 <span class="function"><strong>array()</strong></span></strong></p>
<div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$firstquarter&nbsp;</span><span style="color: #007700">=&nbsp;array(</span><span style="color: #0000BB">1&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #DD0000">'January'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'February'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'March'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">print_r</span><span style="color: #007700">(</span><span style="color: #0000BB">$firstquarter</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
</div>
<div class="example-contents"><p>以上例程会输出:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
Array
(
[1] =&gt; January
[2] =&gt; February
[3] =&gt; March
)
</pre></div>
</div>
</div>
</p>
<p class="para">
在 Perl 中,可以访问在双引号内的数组的值。但在 PHP
中需要将数组用花括号括起来。
<div class="example" id="example-6086">
<p><strong>Example #4 访问双引号内的数组</strong></p>
<div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br />$foo&nbsp;</span><span style="color: #007700">=&nbsp;array(</span><span style="color: #DD0000">'bar'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #DD0000">'baz'</span><span style="color: #007700">);<br />echo&nbsp;</span><span style="color: #DD0000">"Hello&nbsp;</span><span style="color: #007700">{</span><span style="color: #0000BB">$foo</span><span style="color: #007700">[</span><span style="color: #DD0000">'bar'</span><span style="color: #007700">]}</span><span style="color: #DD0000">!"</span><span style="color: #007700">;&nbsp;</span><span style="color: #FF8000">//&nbsp;Hello&nbsp;baz!<br /><br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
</div>
</div>
</p>
</div>
<div class="refsect1 notes" id="refsect1-function.array-notes">
<h3 class="title">注释</h3>
<p class="para">
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
<span class="function"><strong>array()</strong></span> 是一个语言结构,用于字面上表示数组,不是常规的函数。
</p>
</p></blockquote>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.array-seealso">
<h3 class="title">参见</h3>
<p class="para">
<ul class="simplelist">
<li class="member"><span class="function"><a href="array_pad.html" class="function" rel="rdfs-seeAlso">array_pad()</a> - 以指定长度将一个值填充进数组</span></li>
<li class="member"><span class="function"><a href="list.html" class="function" rel="rdfs-seeAlso">list()</a> - 把数组中的值赋给一组变量</span></li>
<li class="member"><span class="function"><a href="count.html" class="function" rel="rdfs-seeAlso">count()</a> - 计算数组中的单元数目,或对象中的属性个数</span></li>
<li class="member"><span class="function"><a href="range.html" class="function" rel="rdfs-seeAlso">range()</a> - 根据范围创建数组,包含指定的元素</span></li>
<li class="member"><a href="control_structures.foreach.html" class="link">foreach</a></li>
<li class="member">The <a href="language.types.array.html" class="link">array</a> type</li>
</ul>
</p>
</div>
</div></div></div></body></html>