array_rand

名稱:array_rand

分類:數組

所屬語言:php

一句話介紹:返回數組中一個或多個隨機的鍵。

實例

例子1

返回包含隨機鍵名的數組：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"yellow"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"brown"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token variable">$random_keys</span> <span class="token operator">=</span><span class="token function"></span></span><mark> <span class="token function">array_rand</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token number">3</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token variable">$a</span> <span class="token punctuation">[</span> <span class="token variable">$random_keys</span> <span class="token punctuation">[</span> <span class="token number">0</span> <span class="token punctuation">]</span> <span class="token punctuation">]</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token variable">$a</span> <span class="token punctuation">[</span> <span class="token variable">$random_keys</span> <span class="token punctuation">[</span> <span class="token number">1</span> <span class="token punctuation">]</span> <span class="token punctuation">]</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token variable">$a</span> <span class="token punctuation">[</span> <span class="token variable">$random_keys</span> <span class="token punctuation">[</span> <span class="token number">2</span> <span class="token punctuation">]</span> <span class="token punctuation">]</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span>

親自試一試

例子2

從數組返回一個隨機鍵：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"a"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"b"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"c"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"d"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"yellow"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_rand</span> <span class="token punctuation">(</span> <span class="token variable">$a</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 punctuation">;</span>
<span class="token delimiter important">?></span>

親自試一試

例子3

返回包含隨機字符串鍵名的數組：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"a"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"b"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"c"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"d"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"yellow"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_rand</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token number">2</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span>

親自試一試