array_walk
使用用户自定义函数对数组中的每个元素做回调处理
对数组中的每个元素应用用户自定义函数:
<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">$value</span><span class="token punctuation">,</span><span class="token variable">$key</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"The key <span class="token interpolation"><span class="token variable">$key</span></span> has the value <span class="token interpolation"><span class="token variable">$value</span></span><br>"</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token variable">$a</span><span class="token operator">=</span><span class="token keyword">array</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"a"</span><span class="token operator">=></span><span class="token string double-quoted-string">"red"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"b"</span><span class="token operator">=></span><span class="token string double-quoted-string">"green"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"c"</span><span class="token operator">=></span><span class="token string double-quoted-string">"blue"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function"></span><mark><span class="token function">array_walk</span><span class="token punctuation">(</span><span class="token variable">$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 delimiter important">?></span></span>
设置一个参数:
<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">$value</span><span class="token punctuation">,</span><span class="token variable">$key</span><span class="token punctuation">,</span><span class="token variable">$p</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token keyword">echo</span> <span class="token string double-quoted-string">"<span class="token interpolation"><span class="token variable">$key</span></span> <span class="token interpolation"><span class="token variable">$p</span></span> <span class="token interpolation"><span class="token variable">$value</span></span><br>"</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token variable">$a</span><span class="token operator">=</span><span class="token keyword">array</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"a"</span><span class="token operator">=></span><span class="token string double-quoted-string">"red"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"b"</span><span class="token operator">=></span><span class="token string double-quoted-string">"green"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"c"</span><span class="token operator">=></span><span class="token string double-quoted-string">"blue"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function"></span><mark><span class="token function">array_walk</span><span class="token punctuation">(</span><span class="token variable">$a</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"myfunction"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"has the value"</span><span class="token punctuation">)</span></mark><span class="token punctuation"></span><span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
更改一个数组元素的值(请注意 &$value):
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">function</span> <span class="token function-definition function">myfunction</span><span class="token punctuation">(</span><span class="token operator">&</span><span class="token variable">$value</span><span class="token punctuation">,</span><span class="token variable">$key</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token variable">$value</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 variable">$a</span><span class="token operator">=</span><span class="token keyword">array</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"a"</span><span class="token operator">=></span><span class="token string double-quoted-string">"red"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"b"</span><span class="token operator">=></span><span class="token string double-quoted-string">"green"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"c"</span><span class="token operator">=></span><span class="token string double-quoted-string">"blue"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function"></span><mark><span class="token function">array_walk</span><span class="token punctuation">(</span><span class="token variable">$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 function">print_r</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 delimiter important">?></span></span>