sizeof

名称:sizeof

分类:数组

所属语言:php

一句话介绍:count() 的别名。

实例

例子 1

返回数组中元素的数目：

<span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$cars</span><span class="token operator">=</span><span class="token keyword">array</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"Volvo"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"BMW"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"Toyota"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword"></span><mark><span class="token keyword">echo</span> <span class="token function">sizeof</span><span class="token punctuation">(</span><span class="token variable">$cars</span><span class="token punctuation">)</span></mark><span class="token punctuation"></span><span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

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例子 2

递归地计算数组中元素的数目：

<span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$cars</span><span class="token operator">=</span><span class="token keyword">array</span>
  <span class="token punctuation">(</span>
  <span class="token string double-quoted-string">"Volvo"</span><span class="token operator">=></span><span class="token keyword">array</span>
  <span class="token punctuation">(</span>
  <span class="token string double-quoted-string">"XC60"</span><span class="token punctuation">,</span>
  <span class="token string double-quoted-string">"XC90"</span>
  <span class="token punctuation">)</span><span class="token punctuation">,</span>
  <span class="token string double-quoted-string">"BMW"</span><span class="token operator">=></span><span class="token keyword">array</span>
  <span class="token punctuation">(</span>
  <span class="token string double-quoted-string">"X3"</span><span class="token punctuation">,</span>
  <span class="token string double-quoted-string">"X5"</span>
  <span class="token punctuation">)</span><span class="token punctuation">,</span>
  <span class="token string double-quoted-string">"Toyota"</span><span class="token operator">=></span><span class="token keyword">array</span>
  <span class="token punctuation">(</span>
  <span class="token string double-quoted-string">"Highlander"</span>
  <span class="token punctuation">)</span>
  <span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token keyword">echo</span> <span class="token string double-quoted-string">"常规计数："</span> <span class="token operator">.</span> <span class="token function"></span><mark><span class="token function">sizeof</span><span class="token punctuation">(</span><span class="token variable">$cars</span><span class="token punctuation">)</span></mark><span class="token punctuation"></span><span class="token operator">.</span><span class="token string double-quoted-string">"<br>"</span><span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"递归计数："</span> <span class="token operator">.</span> <span class="token function"></span><mark><span class="token function">sizeof</span><span class="token punctuation">(</span><span class="token variable">$cars</span><span class="token punctuation">,</span><span class="token number">1</span><span class="token punctuation">)</span></mark><span class="token punctuation"></span><span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

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