array_map
為數組的每個元素應用回調函數
中文(繁體)
中文(繁體)
將函數作用到數組中的每個值上，每個值都乘以本身，並返回帶有新值的數組：
<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">$v</span> <span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">return</span> <span class="token punctuation">(</span> <span class="token variable">$v</span> <span class="token operator">*</span> <span class="token variable">$v</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token number">1</span> <span class="token punctuation">,</span> <span class="token number">2</span> <span class="token punctuation">,</span> <span class="token number">3</span> <span class="token punctuation">,</span> <span class="token number">4</span> <span class="token punctuation">,</span> <span class="token number">5</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_map</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"myfunction"</span> <span class="token punctuation">,</span> <span class="token variable">$a</span> <span class="token punctuation">)</span></mark><span class="token punctuation"></span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span>
使用用戶自定義函數來改變數組的值：
<span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token keyword">function</span> <span class="token function-definition function">myfunction</span> <span class="token punctuation">(</span> <span class="token variable">$v</span> <span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">if</span> <span class="token punctuation">(</span> <span class="token variable">$v</span> <span class="token operator">===</span> <span class="token string double-quoted-string">"Dog"</span> <span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token keyword">return</span> <span class="token string double-quoted-string">"Fido"</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token keyword">return</span> <span class="token variable">$v</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Horse"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Dog"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Cat"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span><span class="token function"></span></span><mark> <span class="token function">array_map</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"myfunction"</span> <span class="token punctuation">,</span> <span class="token variable">$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>
使用兩個數組：
<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">if</span> <span class="token punctuation">(</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 keyword">return</span> <span class="token string double-quoted-string">"same"</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token keyword">return</span> <span class="token string double-quoted-string">"different"</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token variable">$a1</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Horse"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Dog"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Cat"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token variable">$a2</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Cow"</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">"Rat"</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_map</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"myfunction"</span> <span class="token punctuation">,</span> <span class="token variable">$a1</span> <span class="token punctuation">,</span> <span class="token variable">$a2</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>
將數組中值的所有字母改為大寫：
<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">$v</span> <span class="token punctuation">)</span>
<span class="token punctuation">{</span>
<span class="token variable">$v</span> <span class="token operator">=</span> <span class="token function">strtoupper</span> <span class="token punctuation">(</span> <span class="token variable">$v</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token keyword">return</span> <span class="token variable">$v</span> <span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Animal"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"horse"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Type"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"mammal"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token function">array_map</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"myfunction"</span> <span class="token punctuation">,</span> <span class="token variable">$a</span> <span class="token punctuation">)</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>
將函數名賦值為null 時：
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$a1</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Dog"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Cat"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span> <span class="token variable">$a2</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"Puppy"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"Kitten"</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_map</span> <span class="token punctuation">(</span> <span class="token constant">null</span> <span class="token punctuation">,</span> <span class="token variable">$a1</span> <span class="token punctuation">,</span> <span class="token variable">$a2</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>
array_sum
array_diff_ukey
array_chunk
array_key_first
array_intersect_ukey
current
array_walk
sizeof
