Php
/
Array
- 1 Basics 5
-
Quotes
-
Constants
-
Control structures
-
Reference
-
Integers
- 2 Variables 4
-
Definition
-
Naming
-
Exists
-
Type casting
- 3 Operators 5
-
Aritmetic
-
Bitwise
-
String
-
Comparison
-
Logical
- 4 Function 4
-
Definition
-
Anonymous
-
Reference
-
Variable scope
- 5 Array 9
-
Basics
-
Operations
-
Create
-
KeyValue
-
Search
-
Modify
-
Sort
-
Stacks
-
Storage
- 6 String 9
-
Basics
-
Compare
-
Search
-
Replace
-
Format
-
Regexp
-
Parse
-
Formating
-
Json
- 7 Streams 6
-
File open
-
Read file
-
Read csv
-
File contents
-
Context
-
Ob_start
- 8 Oop 6
-
Object instantiation
-
Class constructor
-
Interfaces, abstract
-
Resource visibility
-
Class constants
-
Namespaces
- 9 Features 9
-
Autoload
-
Class reflection
-
Magic methods
-
Exceptions
-
Late static binding
-
Type hinting
-
SPL
-
PHPUNIT
-
PHAR
- 10 Versions 2
-
Php7.4
-
Php8.0
- 11 Http 4
-
Headers
-
File Uploads
-
Cookies
-
Sessions
- 12 Design Patterns 4
-
Singleton Pattern
-
Observer Pattern
-
Strategy Pattern
-
Registry
- 13 Modern Php 8
-
Composer
-
Slim Framework
-
Autoloader
-
Package
-
Releases
-
Generators
-
Dependency Injection
-
Middleware
- 14 Create Framework 7
-
App
-
Http Foundation
-
Front Controller
-
Routing
-
Render Controller
-
Resolver
-
SoC
- 15 Frameworks 4
-
Symfony v5
-
Laravel v8
-
Laminas v3
-
Codeigniter v4
- 16 Composer 5
-
Guzzle
-
Carbon
-
Faker
-
Math
-
Requests
- 17 Symfony 6
-
Routes
-
Annotations
-
Flex
-
Controllers
-
Doctrine
-
Templating
/
Array search
➟
➟
Last update: 20-02-2022
Search
Value Exists
Check if a value exists in an array
$array = array('a'=>1, 'b'=>2, 'c'=>3);
echo in_array(1, $array); // Output: 1
$arr = array ('a' => NULL, 'b' => 2);
echo isset ($arr['a']); // False
echo array_key_exists('a', $arr); // True
Array Search
Array search may return false, always use indentical operator.
$array = array(1,2,3,4);
echo array_search(4, $array); // Output 3
// wrong operator (==)
$array = array(1,2,3,4);
if (array_search(5, $array) == 0) { // true - Look Here
echo 'Found'; // Output: Found!
}
// correct operator (===)
$array = array(1,2,3,4);
if (array_search(5, $array) === 0) { // false - Correct
echo 'Found'; // Output nothing
}
Keys
If the optional search_value is specified, only the keys for that value are returned.
$arr = array('a', 'b', 'a', 'c', 'a', '0', false);
print_r(array_keys($arr)); // [ 0, 1, 2, 3, 4, 5, 6 ]
// Search_value provided
$arr = array('a', 'b', 'a', 'c', 'a', '0', false);
print_r(array_keys($arr, 'a')); // [ 0, 2, 4 ]
// Strict search (identical comparation)
$arr = array('a', 'b', 'a', 'c', 'a', '0', false);
print_r(array_keys($arr, '0')); // [ 5, 6 ] not true
print_r(array_keys($arr, '0', true)); // [ 5 ] corect
➥ Questions