Sorting function PHP removes duplicate elements from an array and sorts by key

1. The role of this function: remove duplicate elements from the array and sort by key name
function assoc_unique($arr, $key) {
$tmp_arr = array();
foreach($arr as $k => $v) {
if(in_array($v[$key], $tmp_arr)) {
unset($arr[$k]);
} else {
$tmp_arr[] = $v[$key];
}
}
sort($arr);
return $arr;
}
Usage example:
$aa = array(
array('id' => 123, 'name' => 'Zhang San'),
array( 'id' => 123, 'name' => '李思'),
array('id' => 124, 'name' => '王五'),
array('id' = > 125, 'name' => 'Zhao Liu'),
array('id' => 126, 'name' => 'Zhao Liu')
);
$key = 'id';
assoc_unique(&$aa, $key);
print_r($aa);

The above introduces the sorting function PHP function to remove duplicate elements in the array and sort by key name, including the sorting function. I hope it will be helpful to friends who are interested in PHP tutorials.