json encode issues in php - php

Question

Given this array:
Array
(
[0] => Array
(
[item_id] => 53
[item_name] => MRA Restaurant
[category_name] => Restaurants
[location_name] => Markhiya
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => MRA Restaurant 01.jpg
[item_image_location] => /images/item/
)
[1] => Array
(
[item_id] => 1
[item_name] => MRA Restaurant Bakery & Sweets
[category_name] => Restaurants
[location_name] => Al Ghanim
[item_description] => Great Kerala-style food and lunch buffet.
[item_comments_count] => 2
[item_likes_count] => 6
[item_image_file] => MRA Restaurant Bakery & Sweets.jpg
[item_image_location] => /images/item/
)
[2] => Array
(
[item_id] => 1486
[item_name] => Al Amrah Palace Cafeteria
[category_name] => Restaurants
[location_name] => Al Doha Al Jadeeda
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => Al Amrah Palace Cafeteria.jpg
[item_image_location] => /images/item/
)
[3] => Array
(
[item_id] => 402
[item_name] => Al Hamra
[category_name] => Restaurants
[location_name] => Musheireb
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => Al Hamra.jpg
[item_image_location] => /images/item/
)
[4] => Array
(
[item_id] => 2902
[item_name] => Al Meera Fereej Bin Omran
[category_name] => malls & hypermarkets
[location_name] => Doha
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => Al Meera Fereej Bin Omran.jpg
[item_image_location] => /images/item/
)
[5] => Array
(
[item_id] => 1150
[item_name] => Al Omraa Patisserie & Sweets
[category_name] => Restaurants
[location_name] => Markhiya
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => Al Omraa Patisserie & Sweets.jpg
[item_image_location] => /images/item/
)
)
When convert to JSON using the code:
$items=array_unique($items,SORT_REGULAR);
header('Content-Type: application/json');
echo json_encode($items);
The output is:
[
{
"item_id": "53",
"item_name": "MRA Restaurant",
"category_name": "Restaurants",
"location_name": "Markhiya",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "MRA Restaurant 01.jpg",
"item_image_location": "/images/item/"
},
{
"item_id": "1",
"item_name": "MRA Restaurant Bakery & Sweets",
"category_name": "Restaurants",
"location_name": "Al Ghanim",
"item_description": "Great Kerala-style food and lunch buffet.",
"item_comments_count": "5",
"item_likes_count": "7",
"item_image_file": "MRA Restaurant Bakery & Sweets.jpg",
"item_image_location": "/images/item/"
},
{
"item_id": "1486",
"item_name": "Al Amrah Palace Cafeteria",
"category_name": "Restaurants",
"location_name": "Al Doha Al Jadeeda",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "Al Amrah Palace Cafeteria.jpg",
"item_image_location": "/images/item/"
},
{
"item_id": "402",
"item_name": "Al Hamra",
"category_name": "Restaurants",
"location_name": "Musheireb",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "Al Hamra.jpg",
"item_image_location": "/images/item/"
},
{
"item_id": "2902",
"item_name": "Al Meera Fereej Bin Omran",
"category_name": "malls & hypermarkets",
"location_name": "Doha",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "Al Meera Fereej Bin Omran.jpg",
"item_image_location": "/images/item/"
},
{
"item_id": "1150",
"item_name": "Al Omraa Patisserie & Sweets",
"category_name": "Restaurants",
"location_name": "Markhiya",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "Al Omraa Patisserie & Sweets.jpg",
"item_image_location": "/images/item/"
}
]
This is working fine, but in the following array:
Array
(
[0] => Array
(
[item_id] => 2
[item_name] => Aalishan
[category_name] => Restaurants
[location_name] => Al Muntazah
[item_description] => Authentic North Indian dishes at reasonable prices.
[item_comments_count] => 0
[item_likes_count] => 6
[item_image_file] => aalishan-al-muntazah 03.jpg
[item_image_location] => /images/item/
)
[1] => Array
(
[item_id] => 403
[item_name] => Aalishan
[category_name] => Restaurants
[location_name] => Westbay
[item_description] =>
[item_comments_count] => 0
[item_likes_count] => 2
[item_image_file] => Abdul Khader Alhallab sweets.jpg
[item_image_location] => /images/item/
)
[4] => Array
(
[item_id] => 844
[item_name] => Jaal Broasted Chicken
[category_name] => Restaurants
[location_name] => Fereej Bin Mahmoud
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => Jaal Broasted Chicken.jpg
[item_image_location] => /images/item/
)
[5] => Array
(
[item_id] => 1140
[item_name] => Jaal Cafeteria
[category_name] => Restaurants
[location_name] => Muaither
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => Jaal Cafeteria.jpg
[item_image_location] => /images/item/
)
[6] => Array
(
[item_id] => 627
[item_name] => Jaal Restaurant
[category_name] => Restaurants
[location_name] => Musheireb
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => Jaal Restaurant.jpg
[item_image_location] => /images/item/
)
[7] => Array
(
[item_id] => 1422
[item_name] => Jaal Restaurant
[category_name] => Restaurants
[location_name] => Muaither
[item_description] =>
[item_comments_count] => 0
[item_likes_count] =>
[item_image_file] => 3716_2015_05_29_10_15_50.jpg
[item_image_location] => /images/item/
)
)
When encoded, the output is:
{
"0": {
"item_id": "2",
"item_name": "Aalishan",
"category_name": "Restaurants",
"location_name": "Al Muntazah",
"item_description": "Authentic North Indian dishes at reasonable prices.",
"item_comments_count": "1",
"item_likes_count": "6",
"item_image_file": "aalishan-al-muntazah 03.jpg",
"item_image_location": "/images/item/"
},
"1": {
"item_id": "403",
"item_name": "Aalishan",
"category_name": "Restaurants",
"location_name": "Westbay",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": "2",
"item_image_file": "Abdul Khader Alhallab sweets.jpg",
"item_image_location": "/images/item/"
},
"4": {
"item_id": "3307",
"item_name": "Faalin baby shop",
"category_name": "brands & Fashions",
"location_name": "Al Mirqab Al Jadeed Doha",
"item_description": "Exclusive kids showroom",
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "4045_2015_09_16_07_26_53.jpg",
"item_image_location": "/images/item/"
},
"5": {
"item_id": "844",
"item_name": "Jaal Broasted Chicken",
"category_name": "Restaurants",
"location_name": "Fereej Bin Mahmoud",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "Jaal Broasted Chicken.jpg",
"item_image_location": "/images/item/"
},
"6": {
"item_id": "1140",
"item_name": "Jaal Cafeteria",
"category_name": "Restaurants",
"location_name": "Muaither",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "Jaal Cafeteria.jpg",
"item_image_location": "/images/item/"
},
"7": {
"item_id": "627",
"item_name": "Jaal Restaurant",
"category_name": "Restaurants",
"location_name": "Musheireb",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "Jaal Restaurant.jpg",
"item_image_location": "/images/item/"
},
"8": {
"item_id": "1422",
"item_name": "Jaal Restaurant",
"category_name": "Restaurants",
"location_name": "Muaither",
"item_description": null,
"item_comments_count": "0",
"item_likes_count": null,
"item_image_file": "3716_2015_05_29_10_15_50.jpg",
"item_image_location": "/images/item/"
}
}
What is the issue behind this encoding of same type array but different output?

Answer 1

The array that gives you faulty output has missing indices. It goes from 1 to 4 and skips 2 and 3. That is why the JSON parser dismisses it as a regular array and starts treating it as an associative array.
This is due to array_unique preserving the keys and not re-indexing. array_values() will re-index the array for you:
echo json_encode(array_values($items));