<p>我有一个多维数组，想要根据特定列中的值进行分组。</p> <p>我想要根据<code>level</code>进行分组，但我事先不知道level的值。所以，我不能像在<code>for</code>循环中那样说<code>while $i &lt; 7</code>，因为我不知道<code>7</code>是level键的最大值，而且即使我知道也不确定我是否需要这样做。</p> <pre class="brush:php;toolbar:false;">[ ['cust' =&gt; 'XT8900', 'type' =&gt; 'standard', 'level' =&gt; 1], ['cust' =&gt; 'XT8944', 'type' =&gt; 'standard', 'level' =&gt; 1], ['cust' =&gt; 'XT8922', 'type' =&gt; 'premier', 'level' =&gt; 3], ['cust' =&gt; 'XT8816', 'type' =&gt; 'permier', 'level' =&gt; 3], ['cust' =&gt; 'XT7434', 'type' =&gt; 'standard', 'level' =&gt; 7], ]</pre> <p>期望的结果：</p> <pre class="brush:php;toolbar:false;">Array ( [1] =&gt; Array ( [0] =&gt; Array ( [cust] =&gt; XT8900 [type] =&gt; standard ) [1] =&gt; Array ( [cust] =&gt; XT8944 [type] =&gt; standard ) ) [3] =&gt; Array ( [2] =&gt; Array ( [cust] =&gt; XT8922 [type] =&gt; premier ) [3] =&gt; Array ( [cust] =&gt; XT8816 [type] =&gt; permier ) ) [7] =&gt; Array ( [4] =&gt; Array ( [cust] =&gt; XT7434 [type] =&gt; standard ) ) )</pre> <p><br /></p>

foreach ($input_arr as $key => &$entry) {
    $level_arr[$entry['level']][$key] = $entry;
}

$templevel=0;   

  $newkey=0;

  $grouparr[$templevel]="";

  foreach ($items as $key => $val) {
   if ($templevel==$val['level']){
     $grouparr[$templevel][$newkey]=$val;
   } else {
     $grouparr[$val['level']][$newkey]=$val;
   }
     $newkey++;       
  }
print($grouparr);

print($grouparr[7]);

[7] => Array (
      [4] => Array (
             [cust] => XT7434
             [type] => standard
             )
      )

print($grouparr[3]);

[3] => Array (
      [2] => Array (
             [cust] => XT8922
             [type] => premier
             )

      [3] => Array (
             [cust] => XT8816
             [type] => permier
             )
      )