uasort
使用用户自定义的比较函数对数组中的值进行排序并保持索引关联
使用用户自定义的比较函数对数组 $arr 中的元素按键值进行排序:
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token keyword">function</span> <span class="token function-definition function">my_sort</span><span class="token punctuation">(</span><span class="token variable">$a</span><span class="token punctuation">,</span><span class="token variable">$b</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token variable">$a</span><span class="token operator">==</span><span class="token variable">$b</span><span class="token punctuation">)</span> <span class="token keyword">return</span> <span class="token number">0</span><span class="token punctuation">;</span> <span class="token keyword">return</span> <span class="token punctuation">(</span><span class="token variable">$a</span><span class="token operator"><</span><span class="token variable">$b</span><span class="token punctuation">)</span><span class="token operator">?</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">:</span><span class="token number">1</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token variable">$arr</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 number">4</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"b"</span><span class="token operator">=></span><span class="token number">2</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"c"</span><span class="token operator">=></span><span class="token number">8</span><span class="token punctuation">,</span>d<span class="token operator">=></span><span class="token string double-quoted-string">"6"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function"></span><mark><span class="token function">uasort</span><span class="token punctuation">(</span><span class="token variable">$arr</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"my_sort"</span><span class="token punctuation">)</span></mark><span class="token punctuation"></span><span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>