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array_reduce

用回調函數迭代地將數組簡化為單一的值
名稱:array_reduce
分類:數組
所屬語言:php
一句話介紹:通過使用用戶自定義函數,以字符串返回數組。

實例

例子1

向用戶自定義函數發送數組中的值,並返回一個字符串:

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token keyword">function</span> <span class="token function-definition function">myfunction</span> <span class="token punctuation">(</span> <span class="token variable">$v1</span> <span class="token punctuation">,</span> <span class="token variable">$v2</span> <span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">return</span> <span class="token variable">$v1</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"-"</span> <span class="token operator">.</span> <span class="token variable">$v2</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Dog"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Cat"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Horse"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_reduce</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"myfunction"</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2

設置initial參數:

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token keyword">function</span> <span class="token function-definition function">myfunction</span> <span class="token punctuation">(</span> <span class="token variable">$v1</span> <span class="token punctuation">,</span> <span class="token variable">$v2</span> <span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">return</span> <span class="token variable">$v1</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"-"</span> <span class="token operator">.</span> <span class="token variable">$v2</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Dog"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Cat"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Horse"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_reduce</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"myfunction"</span> <span class="token punctuation">,</span> <span class="token number">5</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

返回總和:

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token keyword">function</span> <span class="token function-definition function">myfunction</span> <span class="token punctuation">(</span> <span class="token variable">$v1</span> <span class="token punctuation">,</span> <span class="token variable">$v2</span> <span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">return</span> <span class="token variable">$v1</span> <span class="token operator">+</span> <span class="token variable">$v2</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token number">10</span> <span class="token punctuation">,</span> <span class="token number">15</span> <span class="token punctuation">,</span> <span class="token number">20</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_reduce</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"myfunction"</span> <span class="token punctuation">,</span> <span class="token number">5</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

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