sort array by key php code example

Example 1: php sort array by key

$weight = [
    'Pete' => 75, 
    'Benjamin' => 89,
    'Jonathan' => 101
  ];  	
  ksort($weight);

Example 2: php sort array by specific key

usort($array, function ($a, $b) {
  return ($a['specific_key'] < $b['specific_key']) ? -1 : 1;
});

Example 3: php sort array of array by key

$inventory = [
	['price' => 10.99, 'product' => 'foo 1'],
    ['price' => 5.99, 'product' => 'foo 2'],
  	['price' => 100, 'product' => 'foo 3'],
  
];

$price = array_column($inventory, 'price');

array_multisort($price, SORT_DESC, $inventory);

Example 4: php array sort by key value

To PHP sort array by key, you should use: 
	ksort() (for ascending order) or krsort() (for descending order). 
      
To PHP sort array by value, you will need functions:
	asort() and arsort() (for ascending and descending orders).

Example 5: array sort php

// array sort php
$room_details = array(
      "2020-09-27": [
                {
                    "content": "how are you",
                    "detail_id": "1",
                    "time": "17:57:28",
                    "chat_time": "2020-09-24 17:57:28",
                    "width": "0",
                    "height": "0",
                    "type": "1",
                    "distance_time": "26 days ago",
                    "avatar": "uploads/MemberImage/20200922-1436-image-5f699b536f438-0.png",
                    "position": 2
                },
                {
                    "content": "I am fine, thanks",
                    "detail_id": "2",
                    "time": "17:57:45",
                    "chat_time": "2020-09-24 17:57:45",
                    "width": "0",
                    "height": "0",
                    "type": "1",
                    "distance_time": "26 days ago",
                    "avatar": "uploads/MemberImage/20200922-1436-image-5f699b536f438-0.png",
                    "position": 2
                },
      ],
	 "2020-09-24": [
                {
                    "content": "how are you",
                    "detail_id": "1",
                    "time": "17:57:28",
                    "chat_time": "2020-09-24 17:57:28",
                    "width": "0",
                    "height": "0",
                    "type": "1",
                    "distance_time": "26 days ago",
                    "avatar": "uploads/MemberImage/20200922-1436-image-5f699b536f438-0.png",
                    "position": 2
                },
                {
                    "content": "I am fine, thanks",
                    "detail_id": "2",
                    "time": "17:57:45",
                    "chat_time": "2020-09-24 17:57:45",
                    "width": "0",
                    "height": "0",
                    "type": "1",
                    "distance_time": "26 days ago",
                    "avatar": "uploads/MemberImage/20200922-1436-image-5f699b536f438-0.png",
                    "position": 2
                },
      ],
);

sort($room_details);

// result
// array sort php
$room_details = array(
      "2020-09-24": [
                ...
      ],
	 "2020-09-27": [
               ...
      ],
);

Example 6: php order array by specific key

function cmp($a, $b)
    {
        return strcmp($a->display_name, $b->display_name);
    }

    usort($blogusers, "cmp");

    foreach ($blogusers as $bloguser)
    {
        ...