array_keys

實例

例子1

返回包含數組中所有鍵名的一個新數組：

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

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例子2

使用value參數：

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

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例子3

使用strict參數（false）：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token number">10</span> <span class="token punctuation">,</span> <span class="token number">20</span> <span class="token punctuation">,</span> <span class="token number">30</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"10"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_keys</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"10"</span> <span class="token punctuation">,</span> <span class="token constant boolean">false</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>

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例子4

使用strict參數（true）：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token number">10</span> <span class="token punctuation">,</span> <span class="token number">20</span> <span class="token punctuation">,</span> <span class="token number">30</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"10"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_keys</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"10"</span> <span class="token punctuation">,</span> <span class="token constant boolean">true</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