使用内置函数解决PHP多维数组排序问题

学习PHP时，你可能会遇到PHP多维数组排序问题，这里将介绍PHP多维数组排序问题的解决方法，在这里拿出来和大家分享一下，希望对大家有帮助。

根据数组的键进行比较大小，排序，就不用说了，php有很多，很方便的内置函数，krsort(),ksort()等如果是根据数组的值进行比较大小就麻烦一些。如果值没有重复的情况，可以先用array_flip()交换键、值；然后krsort()，然后在array_flip()交换回来，就可以比较大小。有值重复的情况，就要用到一些排序算法了，不过php有很方便的回调函数uasort()会保持原来的索引、usort()会重建索引。PHP多维数组排序代码：

<ol class="dp-xml">
<li class="alt"><span><span class="tag"></span><span class="tag-name">php</span><span> </span></span></li>
<li class=""><span>functioncmp($a,$b){  </span></li>
<li class="alt"><span>if($a[”nums”]==$b[”nums”]){  </span></li>
<li class=""><span>return0;  </span></li>
<li class="alt"><span>}  </span></li>
<li class="">
<span>return($a[”nums”]</span><span class="tag"><span>$b[”nums”])?-1:1;  </span></span>
</li>
<li class="alt"><span>}  </span></li>
<li class="">
<span>$</span><span class="attribute">arr</span><span>=</span><span class="attribute-value">Array</span><span>(  </span>
</li>
<li class="alt">
<span></span><span class="attribute">0</span><span>=</span><span class="tag">></span><span>Array(  </span>
</li>
<li class="">
<span>“username”=</span><span class="tag">></span><span>owen,  </span>
</li>
<li class="alt">
<span>“nums”=</span><span class="tag">></span><span>2,  </span>
</li>
<li class=""><span>),  </span></li>
<li class="alt">
<span></span><span class="attribute">1</span><span>=</span><span class="tag">></span><span>Array(  </span>
</li>
<li class="">
<span>“username”=</span><span class="tag">></span><span>d5s,  </span>
</li>
<li class="alt">
<span>“nums”=</span><span class="tag">></span><span>5,  </span>
</li>
<li class=""><span>),  </span></li>
<li class="alt">
<span></span><span class="attribute">2</span><span>=</span><span class="tag">></span><span>Array(  </span>
</li>
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<span>“username”=</span><span class="tag">></span><span>pt,  </span>
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<li class="alt">
<span>“nums”=</span><span class="tag">></span><span>3,  </span>
</li>
<li class=""><span>),  </span></li>
<li class="alt"><span>);  </span></li>
<li class=""><span>uasort($arr,“cmp”);  </span></li>
<li class="alt">
<span>echo‘</span><span class="tag"><span class="attribute">prestyle</span><span class="tag-name">prestyle</span><span>=”text-align:left”</span><span class="tag">></span><span>’;  </span></span>
</li>
<li class=""><span>print_r($arr);  </span></li>
<li class="alt">
<span>echo‘</span><span class="tag"><span class="tag-name">pre</span><span class="tag">></span><span>’;  </span></span>
</li>
<li class="">
<span></span><span class="tag">?></span><span> </span>
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<li class="alt"><span> </span></li>
<li class=""><span>Array  </span></li>
<li class="alt"><span>(  </span></li>
<li class="">
<span>[0]=</span><span class="tag">></span><span>Array  </span>
</li>
<li class="alt"><span>(  </span></li>
<li class="">
<span>[username]=</span><span class="tag">></span><span>owen  </span>
</li>
<li class="alt">
<span>[nums]=</span><span class="tag">></span><span>2  </span>
</li>
<li class=""><span>)  </span></li>
<li class="alt"><span> </span></li>
<li class="">
<span>[2]=</span><span class="tag">></span><span>Array  </span>
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<li class="alt"><span>(  </span></li>
<li class="">
<span>[username]=</span><span class="tag">></span><span>pt  </span>
</li>
<li class="alt">
<span>[nums]=</span><span class="tag">></span><span>3  </span>
</li>
<li class=""><span>)  </span></li>
<li class="alt"><span> </span></li>
<li class="">
<span>[1]=</span><span class="tag">></span><span>Array  </span>
</li>
<li class="alt"><span>(  </span></li>
<li class="">
<span>[username]=</span><span class="tag">></span><span>d5s  </span>
</li>
<li class="alt">
<span>[nums]=</span><span class="tag">></span><span>5  </span>
</li>
<li class=""><span>)  </span></li>
<li class="alt"><span> </span></li>
<li class=""><span>) </span></li>
</ol>