PHP开发笔记：二维数组根据某一项来进行排序

比如说我们现在有一个二维数组：

$arr = array(
‘d' => array(‘id' => 5, ‘name' => 1, ‘age' => 7),
‘b' => array(‘id' => 2,'name' => 3,'age' => 4),
‘a' => array(‘id' => 8,'name' => 10,'age' => 5),
‘c' => array(‘id' => 1,'name' => 2,'age' => 2)
); 

目标是针对于这个二维数组的每一项，根据他们的age来进行排序，排序过程中我们会使用到PHP内置的array_multisort() 函数：

function multi_array_sort($multi_array,$sort_key,$sort=SORT_ASC){
    if(is_array($multi_array)){
        foreach ($multi_array as $row_array){
            if(is_array($row_array)){
                $key_array[] = $row_array[$sort_key];
            }else{
                return false;
            }
        }
    }else{
        return false;
    }
    array_multisort($key_array,$sort,$multi_array);
    return $multi_array;
} 

我们来看一下实例的处理结果：

echo “<pre/>”;
print_r(multi_array_sort($arr,'age'));exit;
//输出
Array
(
[c] => Array
(
[id] => 1
[name] => 2
[age] => 2
)
[b] => Array
(
[id] => 2
[name] => 3
[age] => 4
)
[a] => Array
(
[id] => 8
[name] => 10
[age] => 5
)
[d] => Array
(
[id] => 5
[name] => 1
[age] => 7
)
)