The toJson() method in Laravel Collection makes it simple to convert the collection into JSON format. It essentially uses PHP's built-in json_encode() function under the hood. If needed, you can also provide the $options parameter, which works similarly to the json_encode function and is a set of predefined JSON constants.

1. Create a new Laravel Project
2. Signature
3. Example 1
4. Output
5. Example 2
6. Output
7. toJson() and Deep Nested Data Structures

Creating the Laravel app is not necessary for this step, but if you haven't done it yet, you can proceed by executing the following command

composer create-project laravel/laravel laravel_collection

The signature of toJson() method in the Illuminate/Support/Collection class looks something like below.

/**
 * Get the collection of items as JSON.
 *
 * @param  int  $options
 * @return string
 */
public function toJson($options = 0)
{
    return json_encode($this->jsonSerialize(), $options);
}

In the example below, we can demonstrate how to use the toJson() method.

<?php

namespace App\Http\Controllers;

use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
use Illuminate\Foundation\Validation\ValidatesRequests;
use Illuminate\Routing\Controller as BaseController;
use Illuminate\Support\Collection;

class Controller extends BaseController
{
    use AuthorizesRequests, ValidatesRequests;


    public function index(){
        $collection = new Collection([
            ['name' =>  'iPhone 11 Pro', 'price'    =>  999],
            ['name' =>  'iPhone 11', 'price'    =>  799],
        ]);

        $jsonValue = $collection->toJson();
        dd($jsonValue);
    }
}

After running the provided code, you will observe the following output for our $jsonValue variable.

"[{"name":"iPhone 11 Pro","price":999},{"name":"iPhone 11","price":799}]"

To format the value for printing, simply use the option JSON_PRETTY_PRINT.

<?php

namespace App\Http\Controllers;

use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
use Illuminate\Foundation\Validation\ValidatesRequests;
use Illuminate\Routing\Controller as BaseController;
use Illuminate\Support\Collection;

class Controller extends BaseController
{
    use AuthorizesRequests, ValidatesRequests;


    public function index(){
        $collection = new Collection([
            ['name' =>  'iPhone 11 Pro', 'price'    =>  999],
            ['name' =>  'iPhone 11', 'price'    =>  799],
        ]);


        $jsonValue = $collection->toJson(JSON_PRETTY_PRINT);
        dd($jsonValue);
    }
}

[
    {
        "name": "iPhone 11 Pro",
        "price": 999
    },
    {
        "name": "iPhone 11",
        "price": 799
    }
]

As I mentioned earlier, the toJson() method uses PHP's json_encode function internally. However, unlike PHP's json_encode method, toJson() doesn't allow you to specify the depth of the array for encoding, and it defaults to a depth of 512.

To convert a collection instance into its JSON with a depth exceeding 512, you can follow this approach.

use Illuminate\Support\Collection;

// Create a new collection instance.
$collection = new Collection([]);

// Replace 512 with the desired depth.
$jsonValue = json_encode(
    $collection->jsonSerialize(),
    0,
    512
);

That's it for today. I hope it'll be helpful in upcoming project. You can also download this source code from GitHub. Thanks for reading. 🙂