


In PHP, how to sort an array by only certain key value pairs of the array, preserving the key names?
When sorting an array based on key-value pairs in PHP, you can use the uasort() function to receive a callback function to compare the key values and retain the key names. For example, to sort employee records by their salary, you can use the uksort() function to extract the salary value from each element for comparison, thereby sorting the records from low to high salary.
Sorting an array based on key value pairs in PHP for a specific key
Sometimes, when sorting an array in PHP , we need to sort them based on specific key value pairs while preserving the key names. This article explains how to achieve this goal.
<?php // 创建一个数组 $arr = [ 'a' => 1, 'b' => 3, 'c' => 2, 'd' => 4, ]; // 使用 uasort() 函数,接收一个回调函数 uksort($arr, function($a, $b) use ($arr) { return $arr[$a] <=> $arr[$b]; }); // 打印排序后的数组,保留键名 print_r($arr);
Practical case: Sorting employee records by employee salary
Suppose there is an array containing employee records:
$employees = [ 'John Doe' => ['salary' => 50000], 'Jane Smith' => ['salary' => 40000], 'Peter Jones' => ['salary' => 60000], ];
In order to sort employee records by salary The employee records are sorted and we use an additional anonymous function to extract the salary from each element in the array:
// 按薪酬排序 uksort($employees, function($a, $b) use ($employees) { return $employees[$a]['salary'] <=> $employees[$b]['salary']; });
Now, the $employees
array will be sorted by employee salary from low to high , while retaining the employee name key.
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