php基础篇-二维数组排序 array_multisort
对2维数组或者多维数组排序是常见的问题,在php中我们有个专门的多维数组排序函数,下面简单介绍下:
array_multisort(array1,sorting order, sorting type,array2,array3..)是对多个数组或多维数组进行排序的函数。
array1 | 必需。规定输入的数组。 |
sorting order | 可选。规定排列顺序。可能的值是 SORT_ASC 和 SORT_DESC。 |
sorting type | 可选。规定排序类型。可能的值是SORT_REGULAR、SORT_NUMERIC和SORT_STRING。 |
array2 | 可选。规定输入的数组。 |
array3 | 可选。规定输入的数组。 |
参数中的数组被当成一个表的列并以行来进行排序 - 这类似 SQL 的 ORDER BY 子句的功能。第一个数组是要排序的主要数组。数组中的行(值)比较为相同的话,就会按照下一个输入数组中相应值的大小进行排序,依此类推。
第一个参数是数组,随后的每一个参数可能是数组,也可能是下面的排序顺序标志(排序标志用于更改默认的排列顺序)之一:
- SORT_ASC - 默认,按升序排列。(A-Z)
- SORT_DESC - 按降序排列。(Z-A)
随后可以指定排序的类型:
- SORT_REGULAR - 默认。将每一项按常规顺序排列。
- SORT_NUMERIC - 将每一项按数字顺序排列。
- SORT_STRING - 将每一项按字母顺序排列
<?php function my_sort($arrays,$sort_key,$sort_order=SORT_ASC,$sort_type=SORT_NUMERIC ){ if(is_array($arrays)){ foreach ($arrays as $array){ if(is_array($array)){ $key_arrays[] = $array[$sort_key]; }else{ return false; } } }else{ return false; } array_multisort($key_arrays,$sort_order,$sort_type,$arrays); return $arrays; } $person = array( array("id"=>1,"name"=>"fj","weight"=>100,"height"=>180), array("id"=>2,"name"=>"tom","weight"=>53,"height"=>150), array("id"=>3,"name"=>"jerry","weight"=>120,"height"=>156), array("id"=>4,"name"=>"bill","weight"=>110,"height"=>190), array("id"=>5,"name"=>"linken","weight"=>80,"height"=>200), array("id"=>6,"name"=>"madana","weight"=>95,"height"=>110), array("id"=>7,"name"=>"jordan","weight"=>70,"height"=>170) ); var_dump($person); $person = my_sort($person,"name",SORT_ASC,SORT_STRING); var_dump($person); $person = my_sort($person,"weight"); var_dump($person); ?>
结果如下:
array (size=7) 0 => array (size=4) "id" => 1 "name" => "fj" (length=2) "weight" => 100 "height" => 180 1 => array (size=4) "id" => 2 "name" => "tom" (length=3) "weight" => 53 "height" => 150 2 => array (size=4) "id" => 3 "name" => "jerry" (length=5) "weight" => 120 "height" => 156 3 => array (size=4) "id" => 4 "name" => "bill" (length=4) "weight" => 110 "height" => 190 4 => array (size=4) "id" => 5 "name" => "linken" (length=6) "weight" => 80 "height" => 200 5 => array (size=4) "id" => 6 "name" => "madana" (length=6) "weight" => 95 "height" => 110 6 => array (size=4) "id" => 7 "name" => "jordan" (length=6) "weight" => 70 "height" => 170
array (size=7) 0 => array (size=4) "id" => 4 "name" => "bill" (length=4) "weight" => 110 "height" => 190 1 => array (size=4) "id" => 1 "name" => "fj" (length=2) "weight" => 100 "height" => 180 2 => array (size=4) "id" => 3 "name" => "jerry" (length=5) "weight" => 120 "height" => 156 3 => array (size=4) "id" => 7 "name" => "jordan" (length=6) "weight" => 70 "height" => 170 4 => array (size=4) "id" => 5 "name" => "linken" (length=6) "weight" => 80 "height" => 200 5 => array (size=4) "id" => 6 "name" => "madana" (length=6) "weight" => 95 "height" => 110 6 => array (size=4) "id" => 2 "name" => "tom" (length=3) "weight" => 53 "height" => 150
array (size=7) 0 => array (size=4) "id" => 2 "name" => "tom" (length=3) "weight" => 53 "height" => 150 1 => array (size=4) "id" => 7 "name" => "jordan" (length=6) "weight" => 70 "height" => 170 2 => array (size=4) "id" => 5 "name" => "linken" (length=6) "weight" => 80 "height" => 200 3 => array (size=4) "id" => 6 "name" => "madana" (length=6) "weight" => 95 "height" => 110 4 => array (size=4) "id" => 1 "name" => "fj" (length=2) "weight" => 100 "height" => 180 5 => array (size=4) "id" => 4 "name" => "bill" (length=4) "weight" => 110 "height" => 190 6 => array (size=4) "id" => 3 "name" => "jerry" (length=5) "weight" => 120 "height" => 156
这里的重点就是,先把要排序的key存到一个一维数组中,然后就可以使用array_multisort()这个函数,将数组按照key进行排序了,当然,这里的排序你完全可以不适用array_multisort()这个函数,仅仅通过foreach遍历也能达到这个效果,但是既然php开发者给我们提供了更好的办法,我们就可以省去不必要的麻烦了。
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