Helper Methods Flashcards
1
Q
What does the Arr::accessible method do?
A
The Arr::accessible method determines if the given value is array accessible:
use Illuminate\Support\Arr;
use Illuminate\Support\Collection;
$isAccessible = Arr::accessible(['a' => 1, 'b' => 2]);
// true
$isAccessible = Arr::accessible(new Collection);
// true
$isAccessible = Arr::accessible('abc');
// false
$isAccessible = Arr::accessible(new stdClass);
// false
2
Q
What does the Arr::add method do?
A
The Arr::add method adds a given key / value pair to an array if the given key doesn’t already exist in the array or is set to null:
use Illuminate\Support\Arr; $array = Arr::add(['name' => 'Desk'], 'price', 100); // ['name' => 'Desk', 'price' => 100] $array = Arr::add(['name' => 'Desk', 'price' => null], 'price', 100); // ['name' => 'Desk', 'price' => 100]
3
Q
What does the Arr::collapse method do?
A
The Arr::collapse method collapses an array of arrays into a single array:
use Illuminate\Support\Arr; $array = Arr::collapse([[1, 2, 3], [4, 5, 6], [7, 8, 9]]); // [1, 2, 3, 4, 5, 6, 7, 8, 9]
4
Q
What does the Arr::crossJoin method do?
A
The Arr::crossJoin method cross joins the given arrays, returning a Cartesian product with all possible permutations:
use Illuminate\Support\Arr;
$matrix = Arr::crossJoin([1, 2], ['a', 'b']);
/*
[
[1, 'a'],
[1, 'b'],
[2, 'a'],
[2, 'b'],
]
*/
$matrix = Arr::crossJoin([1, 2], ['a', 'b'], ['I', 'II']);
/*
[
[1, 'a', 'I'],
[1, 'a', 'II'],
[1, 'b', 'I'],
[1, 'b', 'II'],
[2, 'a', 'I'],
[2, 'a', 'II'],
[2, 'b', 'I'],
[2, 'b', 'II'],
]
*/
5
Q
What does the Arr::divide method do?
A
The Arr::divide method returns two arrays: one containing the keys and the other containing the values of the given array:
use Illuminate\Support\Arr; [$keys, $values] = Arr::divide(['name' => 'Desk']); // $keys: ['name'] // $values: ['Desk']
6
Q
What does the Arr::dot method do?
A
The Arr::dot method flattens a multi-dimensional array into a single level array that uses “dot” notation to indicate depth:
use Illuminate\Support\Arr; $array = ['products' => ['desk' => ['price' => 100]]]; $flattened = Arr::dot($array); // ['products.desk.price' => 100]
7
Q
What does the Arr::except method do?
A
The Arr::except method removes the given key / value pairs from an array:
use Illuminate\Support\Arr; $array = ['name' => 'Desk', 'price' => 100]; $filtered = Arr::except($array, ['price']); // ['name' => 'Desk']
8
Q
What does the Arr::exists method do?
A
The Arr::exists method checks that the given key exists in the provided array:
use Illuminate\Support\Arr; $array = ['name' => 'John Doe', 'age' => 17]; $exists = Arr::exists($array, 'name'); // true $exists = Arr::exists($array, 'salary'); // false
9
Q
What does the Arr::first method do?
A
The Arr::first method returns the first element of an array passing a given truth test:
use Illuminate\Support\Arr;
$array = [100, 200, 300];
$first = Arr::first($array, function (int $value, int $key) {
return $value >= 150;
});
// 200
A default value may also be passed as the third parameter to the method. This value will be returned if no value passes the truth test:
use Illuminate\Support\Arr; $first = Arr::first($array, $callback, $default);
10
Q
What does the Arr::flatten method do?
A
The Arr::flatten method flattens a multi-dimensional array into a single level array:
use Illuminate\Support\Arr; $array = ['name' => 'Joe', 'languages' => ['PHP', 'Ruby']]; $flattened = Arr::flatten($array); // ['Joe', 'PHP', 'Ruby']
11
Q
What does the Arr::forget method do?
A
The Arr::forget method removes a given key / value pair from a deeply nested array using “dot” notation:
use Illuminate\Support\Arr; $array = ['products' => ['desk' => ['price' => 100]]]; Arr::forget($array, 'products.desk'); // ['products' => []]
12
Q
What does the Arr::get method do?
A
The Arr::get method retrieves a value from a deeply nested array using “dot” notation:
use Illuminate\Support\Arr; $array = ['products' => ['desk' => ['price' => 100]]]; $price = Arr::get($array, 'products.desk.price'); // 100
The Arr::get method also accepts a default value, which will be returned if the specified key is not present in the array:
use Illuminate\Support\Arr; $discount = Arr::get($array, 'products.desk.discount', 0); // 0
13
Q
What does the Arr::has method do?
A
The Arr::has method checks whether a given item or items exists in an array using “dot” notation:
use Illuminate\Support\Arr; $array = ['product' => ['name' => 'Desk', 'price' => 100]]; $contains = Arr::has($array, 'product.name'); // true $contains = Arr::has($array, ['product.price', 'product.discount']); // false
14
Q
What does the Arr::hasAny method do?
A
The Arr::hasAny method checks whether any item in a given set exists in an array using “dot” notation:
use Illuminate\Support\Arr; $array = ['product' => ['name' => 'Desk', 'price' => 100]]; $contains = Arr::hasAny($array, 'product.name'); // true $contains = Arr::hasAny($array, ['product.name', 'product.discount']); // true $contains = Arr::hasAny($array, ['category', 'product.discount']); // false
15
Q
What does the Arr::isAssoc method do?
A
The Arr::isAssoc method returns true if the given array is an associative array. An array is considered “associative” if it doesn’t have sequential numerical keys beginning with zero:
use Illuminate\Support\Arr; $isAssoc = Arr::isAssoc(['product' => ['name' => 'Desk', 'price' => 100]]); // true $isAssoc = Arr::isAssoc([1, 2, 3]); // false
16
Q
What does the Arr::isList method do?
A
The Arr::isList method returns true if the given array’s keys are sequential integers beginning from zero:
use Illuminate\Support\Arr; $isList = Arr::isList(['foo', 'bar', 'baz']); // true $isList = Arr::isList(['product' => ['name' => 'Desk', 'price' => 100]]); // false
17
Q
What does the Arr::join method do?
A
The Arr::join method joins array elements with a string. Using this method’s second argument, you may also specify the joining string for the final element of the array:
use Illuminate\Support\Arr; $array = ['Tailwind', 'Alpine', 'Laravel', 'Livewire']; $joined = Arr::join($array, ', '); // Tailwind, Alpine, Laravel, Livewire $joined = Arr::join($array, ', ', ' and '); // Tailwind, Alpine, Laravel and Livewire
18
Q
What does the Arr::keyBy method do?
A
The Arr::keyBy method keys the array by the given key. If multiple items have the same key, only the last one will appear in the new array:
use Illuminate\Support\Arr;
$array = [
['product_id' => 'prod-100', 'name' => 'Desk'],
['product_id' => 'prod-200', 'name' => 'Chair'],
];
$keyed = Arr::keyBy($array, 'product_id');
/*
[
'prod-100' => ['product_id' => 'prod-100', 'name' => 'Desk'],
'prod-200' => ['product_id' => 'prod-200', 'name' => 'Chair'],
]
*/
19
Q
What does the Arr::last method do?
A
The Arr::last method returns the last element of an array passing a given truth test:
use Illuminate\Support\Arr;
$array = [100, 200, 300, 110];
$last = Arr::last($array, function (int $value, int $key) {
return $value >= 150;
});
// 300
A default value may be passed as the third argument to the method. This value will be returned if no value passes the truth test:
use Illuminate\Support\Arr; $last = Arr::last($array, $callback, $default);
20
Q
What does the Arr::map method do?
A
The Arr::map method iterates through the array and passes each value and key to the given callback. The array value is replaced by the value returned by the callback:
use Illuminate\Support\Arr;
$array = ['first' => 'james', 'last' => 'kirk'];
$mapped = Arr::map($array, function (string $value, string $key) {
return ucfirst($value);
});
// ['first' => 'James', 'last' => 'Kirk']
21
Q
What does the Arr::mapSpread method do?
A
The Arr::mapSpread method iterates over the array, passing each nested item value into the given closure. The closure is free to modify the item and return it, thus forming a new array of modified items:
use Illuminate\Support\Arr;
$array = [
[0, 1],
[2, 3],
[4, 5],
[6, 7],
[8, 9],
];
$mapped = Arr::mapSpread($array, function (int $even, int $odd) {
return $even + $odd;
});
/*
[1, 5, 9, 13, 17]
*/
22
Q
What does the Arr::mapWithKeys method do?
A
The Arr::mapWithKeys method iterates through the array and passes each value to the given callback. The callback should return an associative array containing a single key / value pair:
use Illuminate\Support\Arr;
$array = [
[
'name' => 'John',
'department' => 'Sales',
'email' => 'john@example.com',
],
[
'name' => 'Jane',
'department' => 'Marketing',
'email' => 'jane@example.com',
]
];
$mapped = Arr::mapWithKeys($array, function (array $item, int $key) {
return [$item['email'] => $item['name']];
});
/*
[
'john@example.com' => 'John',
'jane@example.com' => 'Jane',
]
*/
23
Q
What does the Arr::only method do?
A
The Arr::only method returns only the specified key / value pairs from the given array:
use Illuminate\Support\Arr; $array = ['name' => 'Desk', 'price' => 100, 'orders' => 10]; $slice = Arr::only($array, ['name', 'price']); // ['name' => 'Desk', 'price' => 100]
24
Q
What does the Arr::pluck method do?
A
The Arr::pluck method retrieves all of the values for a given key from an array:
use Illuminate\Support\Arr;
$array = [
['developer' => ['id' => 1, 'name' => 'Taylor']],
['developer' => ['id' => 2, 'name' => 'Abigail']],
];
$names = Arr::pluck($array, 'developer.name');
// ['Taylor', 'Abigail']
You may also specify how you wish the resulting list to be keyed:
use Illuminate\Support\Arr; $names = Arr::pluck($array, 'developer.name', 'developer.id'); // [1 => 'Taylor', 2 => 'Abigail']
25
What does the Arr::prepend method do?
The Arr::prepend method will push an item onto the beginning of an array:
```
use Illuminate\Support\Arr;
$array = ['one', 'two', 'three', 'four'];
$array = Arr::prepend($array, 'zero');
// ['zero', 'one', 'two', 'three', 'four']
```
If needed, you may specify the key that should be used for the value:
```
use Illuminate\Support\Arr;
$array = ['price' => 100];
$array = Arr::prepend($array, 'Desk', 'name');
// ['name' => 'Desk', 'price' => 100]
```
26
What does the Arr::prependKeysWith method do?
The Arr::prependKeysWith prepends all key names of an associative array with the given prefix:
```
use Illuminate\Support\Arr;
$array = [
'name' => 'Desk',
'price' => 100,
];
$keyed = Arr::prependKeysWith($array, 'product.');
/*
[
'product.name' => 'Desk',
'product.price' => 100,
]
*/
```
27
What does the Arr::pull method do?
The Arr::pull method returns and removes a key / value pair from an array:
```
use Illuminate\Support\Arr;
$array = ['name' => 'Desk', 'price' => 100];
$name = Arr::pull($array, 'name');
// $name: Desk
// $array: ['price' => 100]
```
A default value may be passed as the third argument to the method. This value will be returned if the key doesn't exist:
```
use Illuminate\Support\Arr;
$value = Arr::pull($array, $key, $default);
```
28
What does the Arr::query method do?
The Arr::query method converts the array into a query string:
```
use Illuminate\Support\Arr;
$array = [
'name' => 'Taylor',
'order' => [
'column' => 'created_at',
'direction' => 'desc'
]
];
Arr::query($array);
// name=Taylor&order[column]=created_at&order[direction]=desc
```
29
What does the Arr::random method do?
The Arr::random method returns a random value from an array:
```
use Illuminate\Support\Arr;
$array = [1, 2, 3, 4, 5];
$random = Arr::random($array);
// 4 - (retrieved randomly)
```
You may also specify the number of items to return as an optional second argument. Note that providing this argument will return an array even if only one item is desired:
```
use Illuminate\Support\Arr;
$items = Arr::random($array, 2);
// [2, 5] - (retrieved randomly)
```
30
What does the Arr::set method do?
The Arr::set method sets a value within a deeply nested array using "dot" notation:
```
use Illuminate\Support\Arr;
$array = ['products' => ['desk' => ['price' => 100]]];
Arr::set($array, 'products.desk.price', 200);
// ['products' => ['desk' => ['price' => 200]]]
```
31
What does the Arr::shuffle method do?
The Arr::shuffle method randomly shuffles the items in the array:
```
use Illuminate\Support\Arr;
$array = Arr::shuffle([1, 2, 3, 4, 5]);
// [3, 2, 5, 1, 4] - (generated randomly)
```
32
What does the Arr::sort method do?
The Arr::sort method sorts an array by its values:
```
use Illuminate\Support\Arr;
$array = ['Desk', 'Table', 'Chair'];
$sorted = Arr::sort($array);
// ['Chair', 'Desk', 'Table']
```
You may also sort the array by the results of a given closure:
```
use Illuminate\Support\Arr;
$array = [
['name' => 'Desk'],
['name' => 'Table'],
['name' => 'Chair'],
];
$sorted = array_values(Arr::sort($array, function (array $value) {
return $value['name'];
}));
/*
[
['name' => 'Chair'],
['name' => 'Desk'],
['name' => 'Table'],
]
*/
```
33
What does the Arr::sortDesc method do?
The Arr::sortDesc method sorts an array in descending order by its values:
```
use Illuminate\Support\Arr;
$array = ['Desk', 'Table', 'Chair'];
$sorted = Arr::sortDesc($array);
// ['Table', 'Desk', 'Chair']
```
You may also sort the array by the results of a given closure:
```
use Illuminate\Support\Arr;
$array = [
['name' => 'Desk'],
['name' => 'Table'],
['name' => 'Chair'],
];
$sorted = array_values(Arr::sortDesc($array, function (array $value) {
return $value['name'];
}));
/*
[
['name' => 'Table'],
['name' => 'Desk'],
['name' => 'Chair'],
]
*/
```
34
What does the Arr::sortRecursive method do?
The Arr::sortRecursive method recursively sorts an array using the sort function for numerically indexed sub-arrays and the ksort function for associative sub-arrays:
```
use Illuminate\Support\Arr;
$array = [
['Roman', 'Taylor', 'Li'],
['PHP', 'Ruby', 'JavaScript'],
['one' => 1, 'two' => 2, 'three' => 3],
];
$sorted = Arr::sortRecursive($array);
/*
[
['JavaScript', 'PHP', 'Ruby'],
['one' => 1, 'three' => 3, 'two' => 2],
['Li', 'Roman', 'Taylor'],
]
*/
```
If you would like the results sorted in descending order, you may use the Arr::sortRecursiveDesc method.
`$sorted = Arr::sortRecursiveDesc($array);`
35
What does the Arr::take method do?
The Arr::take method returns a new array with the specified number of items:
```
use Illuminate\Support\Arr;
$array = [0, 1, 2, 3, 4, 5];
$chunk = Arr::take($array, 3);
// [0, 1, 2]
```
You may also pass a negative integer to take the specified number of items from the end of the array:
```
$array = [0, 1, 2, 3, 4, 5];
$chunk = Arr::take($array, -2);
// [4, 5]
```
36
What does the Arr::toCssClasses method do?
The Arr::toCssClasses method conditionally compiles a CSS class string. The method accepts an array of classes where the array key contains the class or classes you wish to add, while the value is a boolean expression. If the array element has a numeric key, it will always be included in the rendered class list:
```
use Illuminate\Support\Arr;
$isActive = false;
$hasError = true;
$array = ['p-4', 'font-bold' => $isActive, 'bg-red' => $hasError];
$classes = Arr::toCssClasses($array);
/*
'p-4 bg-red'
*/
```
37
What does the Arr::toCssStyles method do?
The Arr::toCssStyles conditionally compiles a CSS style string. The method accepts an array of classes where the array key contains the class or classes you wish to add, while the value is a boolean expression. If the array element has a numeric key, it will always be included in the rendered class list:
```
use Illuminate\Support\Arr;
$hasColor = true;
$array = ['background-color: blue', 'color: blue' => $hasColor];
$classes = Arr::toCssStyles($array);
/*
'background-color: blue; color: blue;'
*/
```
38
What does the Arr::undot method do?
The Arr::undot method expands a single-dimensional array that uses "dot" notation into a multi-dimensional array:
```
use Illuminate\Support\Arr;
$array = [
'user.name' => 'Kevin Malone',
'user.occupation' => 'Accountant',
];
$array = Arr::undot($array);
// ['user' => ['name' => 'Kevin Malone', 'occupation' => 'Accountant']]
```
39
What does the Arr::where method do?
The Arr::where method filters an array using the given closure:
```
use Illuminate\Support\Arr;
$array = [100, '200', 300, '400', 500];
$filtered = Arr::where($array, function (string|int $value, int $key) {
return is_string($value);
});
// [1 => '200', 3 => '400']
```
40
What does the whereNotNull method do?
The Arr::whereNotNull method removes all null values from the given array:
```
use Illuminate\Support\Arr;
$array = [0, null];
$filtered = Arr::whereNotNull($array);
// [0 => 0]
```
41
What does the Arr::wrap method do?
The Arr::wrap method wraps the given value in an array. If the given value is already an array it will be returned without modification:
```
use Illuminate\Support\Arr;
$string = 'Laravel';
$array = Arr::wrap($string);
// ['Laravel']
```
If the given value is null, an empty array will be returned:
```
use Illuminate\Support\Arr;
$array = Arr::wrap(null);
// []
```
42
What does the data_fill method do?
The data_fill function sets a missing value within a nested array or object using "dot" notation:
```
$data = ['products' => ['desk' => ['price' => 100]]];
data_fill($data, 'products.desk.price', 200);
// ['products' => ['desk' => ['price' => 100]]]
data_fill($data, 'products.desk.discount', 10);
// ['products' => ['desk' => ['price' => 100, 'discount' => 10]]]
```
This function also accepts asterisks as wildcards and will fill the target accordingly:
```
$data = [
'products' => [
['name' => 'Desk 1', 'price' => 100],
['name' => 'Desk 2'],
],
];
data_fill($data, 'products.*.price', 200);
/*
[
'products' => [
['name' => 'Desk 1', 'price' => 100],
['name' => 'Desk 2', 'price' => 200],
],
]
*/
```
43
What does data_get do?
The data_get function retrieves a value from a nested array or object using "dot" notation:
```
$data = ['products' => ['desk' => ['price' => 100]]];
$price = data_get($data, 'products.desk.price');
// 100
```
The data_get function also accepts a default value, which will be returned if the specified key is not found:
```
$discount = data_get($data, 'products.desk.discount', 0);
// 0
```
The function also accepts wildcards using asterisks, which may target any key of the array or object:
```
$data = [
'product-one' => ['name' => 'Desk 1', 'price' => 100],
'product-two' => ['name' => 'Desk 2', 'price' => 150],
];
data_get($data, '*.name');
// ['Desk 1', 'Desk 2'];
```
The {first} and {last} placeholders may be used to retrieve the first or last items in an array:
```
$flight = [
'segments' => [
['from' => 'LHR', 'departure' => '9:00', 'to' => 'IST', 'arrival' => '15:00'],
['from' => 'IST', 'departure' => '16:00', 'to' => 'PKX', 'arrival' => '20:00'],
],
];
data_get($flight, 'segments.{first}.arrival');
// 15:00
```
44
What does data_set do?
The data_set function sets a value within a nested array or object using "dot" notation:
```
$data = ['products' => ['desk' => ['price' => 100]]];
data_set($data, 'products.desk.price', 200);
// ['products' => ['desk' => ['price' => 200]]]
```
This function also accepts wildcards using asterisks and will set values on the target accordingly:
```
$data = [
'products' => [
['name' => 'Desk 1', 'price' => 100],
['name' => 'Desk 2', 'price' => 150],
],
];
data_set($data, 'products.*.price', 200);
/*
[
'products' => [
['name' => 'Desk 1', 'price' => 200],
['name' => 'Desk 2', 'price' => 200],
],
]
*/
```
By default, any existing values are overwritten. If you wish to only set a value if it doesn't exist, you may pass false as the fourth argument to the function:
```
$data = ['products' => ['desk' => ['price' => 100]]];
data_set($data, 'products.desk.price', 200, overwrite: false);
// ['products' => ['desk' => ['price' => 100]]]
```
45
What does data_forget do?
The data_forget function removes a value within a nested array or object using "dot" notation:
```
$data = ['products' => ['desk' => ['price' => 100]]];
data_forget($data, 'products.desk.price');
// ['products' => ['desk' => []]]
```
This function also accepts wildcards using asterisks and will remove values on the target accordingly:
```
$data = [
'products' => [
['name' => 'Desk 1', 'price' => 100],
['name' => 'Desk 2', 'price' => 150],
],
];
data_forget($data, 'products.*.price');
/*
[
'products' => [
['name' => 'Desk 1'],
['name' => 'Desk 2'],
],
]
*/
```
46
What does head() do?
The head function returns the first element in the given array:
```
$array = [100, 200, 300];
$first = head($array);
// 100
```
47
What does last() do?
The last function returns the last element in the given array:
```
$array = [100, 200, 300];
$last = last($array);
// 300
```
48
What does the app_path method do?
The app_path function returns the fully qualified path to your application's app directory. You may also use the app_path function to generate a fully qualified path to a file relative to the application directory:
```
$path = app_path();
$path = app_path('Http/Controllers/Controller.php');
```
49
What does the base_path method do?
The base_path function returns the fully qualified path to your application's root directory. You may also use the base_path function to generate a fully qualified path to a given file relative to the project root directory:
```
$path = base_path();
$path = base_path('vendor/bin');
```
50
What does the config_path method do?
The config_path function returns the fully qualified path to your application's config directory. You may also use the config_path function to generate a fully qualified path to a given file within the application's configuration directory:
```
$path = config_path();
$path = config_path('app.php');
```
51
What does the database_path method do?
The database_path function returns the fully qualified path to your application's database directory. You may also use the database_path function to generate a fully qualified path to a given file within the database directory:
```
$path = database_path();
$path = database_path('factories/UserFactory.php');
```
52
What does the lang_path method do?
The lang_path function returns the fully qualified path to your application's lang directory. You may also use the lang_path function to generate a fully qualified path to a given file within the directory:
```
$path = lang_path();
$path = lang_path('en/messages.php');
```
By default, the Laravel application skeleton does not include the lang directory. If you would like to customize Laravel's language files, you may publish them via the lang:publish Artisan command.
53
What does the mix method do?
The mix function returns the path to a versioned Mix file:
`$path = mix('css/app.css');`
54
What does the public_path method do?
The public_path function returns the fully qualified path to your application's public directory. You may also use the public_path function to generate a fully qualified path to a given file within the public directory:
```
$path = public_path();
$path = public_path('css/app.css');
```
55
What does the resource_path method do?
The resource_path function returns the fully qualified path to your application's resources directory. You may also use the resource_path function to generate a fully qualified path to a given file within the resources directory:
```
$path = resource_path();
$path = resource_path('sass/app.scss');
```
56
What does the storage_path method do?
The storage_path function returns the fully qualified path to your application's storage directory. You may also use the storage_path function to generate a fully qualified path to a given file within the storage directory:
```
$path = storage_path();
$path = storage_path('app/file.txt');
```
57
What does action() do?
The action function generates a URL for the given controller action:
```
use App\Http\Controllers\HomeController;
$url = action([HomeController::class, 'index']);
```
If the method accepts route parameters, you may pass them as the second argument to the method:
`$url = action([UserController::class, 'profile'], ['id' => 1]);`
58
What does asset() do?
The asset function generates a URL for an asset using the current scheme of the request (HTTP or HTTPS):
`$url = asset('img/photo.jpg');`
You can configure the asset URL host by setting the ASSET_URL variable in your .env file. This can be useful if you host your assets on an external service like Amazon S3 or another CDN:
```
// ASSET_URL=http://example.com/assets
$url = asset('img/photo.jpg'); // http://example.com/assets/img/photo.jpg
```
59
What does route() do?
The route function generates a URL for a given named route:
`$url = route('route.name');`
If the route accepts parameters, you may pass them as the second argument to the function:
`$url = route('route.name', ['id' => 1]);`
By default, the route function generates an absolute URL. If you wish to generate a relative URL, you may pass false as the third argument to the function:
`$url = route('route.name', ['id' => 1], false);`
60
What does secure_asset() do?
The secure_asset function generates a URL for an asset using HTTPS:
`$url = secure_asset('img/photo.jpg');`
61
What does secure_url() do?
The secure_url function generates a fully qualified HTTPS URL to the given path. Additional URL segments may be passed in the function's second argument:
```
$url = secure_url('user/profile');
$url = secure_url('user/profile', [1]);
```
62
What does to_route() do?
The to_route function generates a redirect HTTP response for a given named route:
`return to_route('users.show', ['user' => 1]);`
If necessary, you may pass the HTTP status code that should be assigned to the redirect and any additional response headers as the third and fourth arguments to the to_route method:
`return to_route('users.show', ['user' => 1], 302, ['X-Framework' => 'Laravel']);`
63
What does url() do?
The url function generates a fully qualified URL to the given path:
```
$url = url('user/profile');
$url = url('user/profile', [1]);
```
If no path is provided, an Illuminate\Routing\UrlGenerator instance is returned:
```
$current = url()->current();
$full = url()->full();
$previous = url()->previous();
```
64
What does abort() do?
The abort function throws an HTTP exception which will be rendered by the exception handler:
`abort(403);`
You may also provide the exception's message and custom HTTP response headers that should be sent to the browser:
`abort(403, 'Unauthorized.', $headers);`
65
What does abort_if() do?
The abort_if function throws an HTTP exception if a given boolean expression evaluates to true:
`abort_if(! Auth::user()->isAdmin(), 403);`
Like the abort method, you may also provide the exception's response text as the third argument and an array of custom response headers as the fourth argument to the function.
66
What does abort_unless() do?
The abort_unless function throws an HTTP exception if a given boolean expression evaluates to false:
`abort_unless(Auth::user()->isAdmin(), 403);`
Like the abort method, you may also provide the exception's response text as the third argument and an array of custom response headers as the fourth argument to the function.
67
What does app() do?
The app function returns the service container instance:
`$container = app();`
You may pass a class or interface name to resolve it from the container:
`$api = app('HelpSpot\API');`
68
What does auth() do?
The auth function returns an authenticator instance. You may use it as an alternative to the Auth facade:
`$user = auth()->user();`
If needed, you may specify which guard instance you would like to access:
`$user = auth('admin')->user();`
69
What does back() do?
The back function generates a redirect HTTP response to the user's previous location:
```
return back($status = 302, $headers = [], $fallback = '/');
return back();
```
70
What does bcrypt() do?
The bcrypt function hashes the given value using Bcrypt. You may use this function as an alternative to the Hash facade:
`$password = bcrypt('my-secret-password');`
71
What does blank() do?
The blank function determines whether the given value is "blank":
```
blank('');
blank(' ');
blank(null);
blank(collect());
// true
blank(0);
blank(true);
blank(false);
// false
```
For the inverse of blank, see the filled method.
72
What does broadcast() do?
The broadcast function broadcasts the given event to its listeners:
```
broadcast(new UserRegistered($user));
broadcast(new UserRegistered($user))->toOthers();
```
73
What does cache() do?
The cache function may be used to get values from the cache. If the given key does not exist in the cache, an optional default value will be returned:
```
$value = cache('key');
$value = cache('key', 'default');
```
You may add items to the cache by passing an array of key / value pairs to the function. You should also pass the number of seconds or duration the cached value should be considered valid:
```
cache(['key' => 'value'], 300);
cache(['key' => 'value'], now()->addSeconds(10));
```
74
What does class_uses_recursive() do?
The class_uses_recursive function returns all traits used by a class, including traits used by all of its parent classes:
`$traits = class_uses_recursive(App\Models\User::class);`
75
What does config() do?
The config function gets the value of a configuration variable. The configuration values may be accessed using "dot" syntax, which includes the name of the file and the option you wish to access. A default value may be specified and is returned if the configuration option does not exist:
```
$value = config('app.timezone');
$value = config('app.timezone', $default);
```
You may set configuration variables at runtime by passing an array of key / value pairs. However, note that this function only affects the configuration value for the current request and does not update your actual configuration values:
`config(['app.debug' => true]);`
75
What does collect() do?
The collect function creates a collection instance from the given value:
`$collection = collect(['taylor', 'abigail']);`
76
What does context() do?
The context function gets the value from the current context. A default value may be specified and is returned if the context key does not exist:
```
$value = context('trace_id');
$value = context('trace_id', $default);
```
You may set context values by passing an array of key / value pairs:
```
use Illuminate\Support\Str;
context(['trace_id' => Str::uuid()->toString()]);
```
77
What does cookie() do?
The cookie function creates a new cookie instance:
`$cookie = cookie('name', 'value', $minutes);`
78
What does csrf_field() do?
The csrf_field function generates an HTML hidden input field containing the value of the CSRF token. For example, using Blade syntax:
`{{ csrf_field() }}`
79
What does csrf_token() do?
The csrf_token function retrieves the value of the current CSRF token:
`$token = csrf_token();`
80
What does decrypt() do?
The decrypt function decrypts the given value. You may use this function as an alternative to the Crypt facade:
`$password = decrypt($value);`
81
What does dd() do?
The dd function dumps the given variables and ends the execution of the script:
```
dd($value);
dd($value1, $value2, $value3, ...);
```
If you do not want to halt the execution of your script, use the dump function instead.
82
What does dispatch() do?
The dispatch function pushes the given job onto the Laravel job queue:
`dispatch(new App\Jobs\SendEmails);`
83
What does dispatch_sync() do?
The dispatch_sync function pushes the given job to the sync queue so that it is processed immediately:
`dispatch_sync(new App\Jobs\SendEmails);`
84
What does dump() do?
The dump function dumps the given variables:
```
dump($value);
dump($value1, $value2, $value3, ...);
```
If you want to stop executing the script after dumping the variables, use the dd function instead.
85
What does encrypt() do?
The encrypt function encrypts the given value. You may use this function as an alternative to the Crypt facade:
`$secret = encrypt('my-secret-value');`
86
What does env() do?
The env function retrieves the value of an environment variable or returns a default value:
```
$env = env('APP_ENV');
$env = env('APP_ENV', 'production');
```
If you execute the config:cache command during your deployment process, you should be sure that you are only calling the env function from within your configuration files. Once the configuration has been cached, the .env file will not be loaded and all calls to the env function will return null.
87
What does event() do?
The event function dispatches the given event to its listeners:
`event(new UserRegistered($user));`
88
What does fake() do?
The fake function resolves a Faker singleton from the container, which can be useful when creating fake data in model factories, database seeding, tests, and prototyping views:
```
@for($i = 0; $i < 10; $i++)
- Name
- {{ fake()->name() }}
- {{ fake()->unique()->safeEmail() }}
89
What does filled() do?
The filled function determines whether the given value is not "blank":
```
filled(0);
filled(true);
filled(false);
// true
filled('');
filled(' ');
filled(null);
filled(collect());
// false
```
For the inverse of filled, see the blank method.
90
What does info() do?
The info function will write information to your application's log:
`info('Some helpful information!');`
An array of contextual data may also be passed to the function:
`info('User login attempt failed.', ['id' => $user->id]);`
91
What does literal() do?
The literal function creates a new stdClass instance with the given named arguments as properties:
```
$obj = literal(
name: 'Joe',
languages: ['PHP', 'Ruby'],
);
$obj->name; // 'Joe'
$obj->languages; // ['PHP', 'Ruby']
```
92
What does logger() do?
The logger function can be used to write a debug level message to the log:
`logger('Debug message');`
An array of contextual data may also be passed to the function:
`logger('User has logged in.', ['id' => $user->id]);`
A logger instance will be returned if no value is passed to the function:
`logger()->error('You are not allowed here.');`
93
What does method_field() do?
The method_field function generates an HTML hidden input field containing the spoofed value of the form's HTTP verb. For example, using Blade syntax:
```
```
94
What does now() do?
The now function creates a new Illuminate\Support\Carbon instance for the current time:
`$now = now();`
95
What does old() do?
The old function retrieves an old input value flashed into the session:
```
$value = old('value');
$value = old('value', 'default');
```
Since the "default value" provided as the second argument to the old function is often an attribute of an Eloquent model, Laravel allows you to simply pass the entire Eloquent model as the second argument to the old function. When doing so, Laravel will assume the first argument provided to the old function is the name of the Eloquent attribute that should be considered the "default value":
```
{{ old('name', $user->name) }}
// Is equivalent to...
{{ old('name', $user) }}
```
96
What does once() do?
The once function executes the given callback and caches the result in memory for the duration of the request. Any subsequent calls to the once function with the same callback will return the previously cached result:
```
function random(): int
{
return once(function () {
return random_int(1, 1000);
});
}
random(); // 123
random(); // 123 (cached result)
random(); // 123 (cached result)
```
When the once function is executed from within an object instance, the cached result will be unique to that object instance:
```
[1, 2, 3]);
}
}
$service = new NumberService;
$service->all();
$service->all(); // (cached result)
$secondService = new NumberService;
$secondService->all();
$secondService->all(); // (cached result)
```
97
What does optional() do?
The optional function accepts any argument and allows you to access properties or call methods on that object. If the given object is null, properties and methods will return null instead of causing an error:
```
return optional($user->address)->street;
{!! old('name', optional($user)->name) !!}
```
The optional function also accepts a closure as its second argument. The closure will be invoked if the value provided as the first argument is not null:
```
return optional(User::find($id), function (User $user) {
return $user->name;
});
```
98
What does policy() do?
The policy method retrieves a policy instance for a given class:
`$policy = policy(App\Models\User::class);`
99
What does redirect() do?
The redirect function returns a redirect HTTP response, or returns the redirector instance if called with no arguments:
```
return redirect($to = null, $status = 302, $headers = [], $https = null);
return redirect('/home');
return redirect()->route('route.name');
```
100
What does report() do?
The report function will report an exception using your exception handler:
`report($e);`
The report function also accepts a string as an argument. When a string is given to the function, the function will create an exception with the given string as its message:
`report('Something went wrong.');`
101
What does report_if() do?
The report_if function will report an exception using your exception handler if the given condition is true:
```
report_if($shouldReport, $e);
report_if($shouldReport, 'Something went wrong.');
```
102
What does report_unless() do?
The report_unless function will report an exception using your exception handler if the given condition is false:
```
report_unless($reportingDisabled, $e);
report_unless($reportingDisabled, 'Something went wrong.');
```
103
What does request() do?
The request function returns the current request instance or obtains an input field's value from the current request:
```
$request = request();
$value = request('key', $default);
```
104
What does rescue() do?
The rescue function executes the given closure and catches any exceptions that occur during its execution. All exceptions that are caught will be sent to your exception handler; however, the request will continue processing:
```
return rescue(function () {
return $this->method();
});
```
You may also pass a second argument to the rescue function. This argument will be the "default" value that should be returned if an exception occurs while executing the closure:
```
return rescue(function () {
return $this->method();
}, false);
return rescue(function () {
return $this->method();
}, function () {
return $this->failure();
});
```
A report argument may be provided to the rescue function to determine if the exception should be reported via the report function:
```
return rescue(function () {
return $this->method();
}, report: function (Throwable $throwable) {
return $throwable instanceof InvalidArgumentException;
});
```
105
What does resolve() do?
The resolve function resolves a given class or interface name to an instance using the service container:
`$api = resolve('HelpSpot\API');`
106
What does response() do?
The response function creates a response instance or obtains an instance of the response factory:
```
return response('Hello World', 200, $headers);
return response()->json(['foo' => 'bar'], 200, $headers);
```
107
What does retry() do?
The retry function attempts to execute the given callback until the given maximum attempt threshold is met. If the callback does not throw an exception, its return value will be returned. If the callback throws an exception, it will automatically be retried. If the maximum attempt count is exceeded, the exception will be thrown:
```
return retry(5, function () {
// Attempt 5 times while resting 100ms between attempts...
}, 100);
```
If you would like to manually calculate the number of milliseconds to sleep between attempts, you may pass a closure as the third argument to the retry function:
```
use Exception;
return retry(5, function () {
// ...
}, function (int $attempt, Exception $exception) {
return $attempt * 100;
});
```
For convenience, you may provide an array as the first argument to the retry function. This array will be used to determine how many milliseconds to sleep between subsequent attempts:
```
return retry([100, 200], function () {
// Sleep for 100ms on first retry, 200ms on second retry...
});
```
To only retry under specific conditions, you may pass a closure as the fourth argument to the retry function:
```
use Exception;
return retry(5, function () {
// ...
}, 100, function (Exception $exception) {
return $exception instanceof RetryException;
});
```
108
What does session() do?
The session function may be used to get or set session values:
`$value = session('key');`
You may set values by passing an array of key / value pairs to the function:
`session(['chairs' => 7, 'instruments' => 3]);`
The session store will be returned if no value is passed to the function:
```
$value = session()->get('key');
session()->put('key', $value);
```
109
What does tap() do?
The tap function accepts two arguments: an arbitrary $value and a closure. The $value will be passed to the closure and then be returned by the tap function. The return value of the closure is irrelevant:
```
$user = tap(User::first(), function (User $user) {
$user->name = 'taylor';
$user->save();
});
```
If no closure is passed to the tap function, you may call any method on the given $value. The return value of the method you call will always be $value, regardless of what the method actually returns in its definition. For example, the Eloquent update method typically returns an integer. However, we can force the method to return the model itself by chaining the update method call through the tap function:
```
$user = tap($user)->update([
'name' => $name,
'email' => $email,
]);
```
To add a tap method to a class, you may add the Illuminate\Support\Traits\Tappable trait to the class. The tap method of this trait accepts a Closure as its only argument. The object instance itself will be passed to the Closure and then be returned by the tap method:
```
return $user->tap(function (User $user) {
// ...
});
```
110
What does throw_if() do?
The throw_if function throws the given exception if a given boolean expression evaluates to true:
```
throw_if(! Auth::user()->isAdmin(), AuthorizationException::class);
throw_if(
! Auth::user()->isAdmin(),
AuthorizationException::class,
'You are not allowed to access this page.'
);
```
111
What does throw_unless() do?
The throw_unless function throws the given exception if a given boolean expression evaluates to false:
```
throw_unless(Auth::user()->isAdmin(), AuthorizationException::class);
throw_unless(
Auth::user()->isAdmin(),
AuthorizationException::class,
'You are not allowed to access this page.'
);
```
112
What does today() do?
The today function creates a new Illuminate\Support\Carbon instance for the current date:
`$today = today();`
113
What does trait_uses_recursive() do?
The trait_uses_recursive function returns all traits used by a trait:
`$traits = trait_uses_recursive(\Illuminate\Notifications\Notifiable::class);`
114
What does transform() do?
The transform function executes a closure on a given value if the value is not blank and then returns the return value of the closure:
```
$callback = function (int $value) {
return $value * 2;
};
$result = transform(5, $callback);
// 10
```
A default value or closure may be passed as the third argument to the function. This value will be returned if the given value is blank:
```
$result = transform(null, $callback, 'The value is blank');
// The value is blank
```
115
What does validator() do?
The validator function creates a new validator instance with the given arguments. You may use it as an alternative to the Validator facade:
`$validator = validator($data, $rules, $messages);`
116
What does value() do?
The value function returns the value it is given. However, if you pass a closure to the function, the closure will be executed and its returned value will be returned:
```
$result = value(true);
// true
$result = value(function () {
return false;
});
// false
```
Additional arguments may be passed to the value function. If the first argument is a closure then the additional parameters will be passed to the closure as arguments, otherwise they will be ignored:
```
$result = value(function (string $name) {
return $name;
}, 'Taylor');
// 'Taylor'
```
117
What does view() do?
The view function retrieves a view instance:
`return view('auth.login');`
118
What does with() do?
The with function returns the value it is given. If a closure is passed as the second argument to the function, the closure will be executed and its returned value will be returned:
```
$callback = function (mixed $value) {
return is_numeric($value) ? $value * 2 : 0;
};
$result = with(5, $callback);
// 10
$result = with(null, $callback);
// 0
$result = with(5, null);
// 5
```
