二维数组排序,且下标重新排
如题,我对某字段排序,排好后,发现下标也跟着走,希望下标重新排,从0~开始排,问怎么做?
------解决方案--------------------
- PHP code
$fruits = array("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple"); ksort($fruits); print "<pre class="brush:php;toolbar:false">"; var_dump($fruits); <br><font color="#e78608">------解决方案--------------------</font><br>
- PHP code
$ar = array( array("10", 11, 100, 100, "a"), array( 1, 2, "2", 3, 1) ); array_multisort($ar[0], SORT_ASC, SORT_STRING, $ar[1], SORT_NUMERIC, SORT_DESC); //SORT_ASC, SORT_DESC, SORT_REGULAR,SORT_NUMERIC, SORT_STRING print "<pre class="brush:php;toolbar:false">"; print_r($ar); <br><font color="#e78608">------解决方案--------------------</font><br> 我想你需要这个――<br>看清楚最后一段代码的最后一个参数<br><br><br>Example #4 对数据库结果进行排序<br><br><br> 本例中 data数组中的每个单元表示一个表中的一行。这是典型的数据库记录的数据集合。 <br><br><br>例子中的数据如下: <br><br><br>volume | edition<br>-------+--------<br> 67 | 2<br> 86 | 1<br> 85 | 6<br> 98 | 2<br> 86 | 6<br> 67 | 7<br><br><br> 数据全都存放在名为 data的数组中。这通常是通过循环从数据库取得的结果,例如 mysql_fetch_assoc()。 <br><br><br><?php <br />$data[] = array('volume' => 67, 'edition' => 2);<br>$data[] = array('volume' => 86, 'edition' => 1);<br>$data[] = array('volume' => 85, 'edition' => 6);<br>$data[] = array('volume' => 98, 'edition' => 2);<br>$data[] = array('volume' => 86, 'edition' => 6);<br>$data[] = array('volume' => 67, 'edition' => 7);<br>?> <br><br><br>本例中将把 volume 降序排列,把 edition 升序排列。 <br><br><br>现在有了包含有行的数组,但是 array_multisort()需要一个包含列的数组,因此用以下代码来取得列,然后排序。 <br><br><br><?php <br />// 取得列的列表<br>foreach ($data as $key => $row) {<br> $volume[$key] = $row['volume'];<br> $edition[$key] = $row['edition'];<br>}<br><br>// 将数据根据 volume 降序排列,根据 edition 升序排列<br>// 把 $data 作为最后一个参数,以通用键排序<br>array_multisort($volume, SORT_DESC, $edition, SORT_ASC, $data);<br>?> <br><br><br>数据集合现在排好序了,结果如下: <br><br><br>volume | edition<br>-------+--------<br> 98 | 2<br> 86 | 1<br> 86 | 6<br> 85 | 6<br> 67 | 2<br> 67 | 7<br><br><br> <br><font color="#e78608">------解决方案--------------------</font><br> 设 $t 是排序的结果,下标不是升序的<br>则 $t = array_values($t);<br>就可化为下标升序的了 <div class="clear"> </div>

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