What is Array in PHP?

PHP arrays is a type of data structure that can hold multiple values of similar type in a single variable.

The Advantage of PHP Array is

• Less Code: We don’t need to define multiple variables.
• Easy to traverse: By using single loop, we can traverse all the elements of an array.
• Sorting: We can sort the elements of array.

There are 3 types of array in PHP.

1. Indexed Array
2. Associative Array
3. Multidimensional Array

1. Indexed Array:

An indexed array is a type of array where each element is assigned a numeric index, starting from 0 and increasing by 1 for each subsequent element.

There are two ways to define indexed array:

1st way:

$animals= array("dog", "cat", "donkey", "monkey");

Example:

<?php  
$animals=array("dog", "cat", "donkey", "monkey");
echo "animals are: $animals[0], $animals[1], $animals[2] and $animals[3]";  
?>  

Output:

animals are: dog, cat, donkey, monkey

2nd way:

$animals [0]="dog";  
$animals [1]="cat";  
$animals [2]="donkey";  
$animals [3]="monkey";  

Example:

<?php  
$animals [0]="summer";  
$animals [1]="winter";  
$animals [2]="spring";  
$animals [3]="autumn";  
echo "animals are: $animals [0], $animals [1], $animals [2] and $animals [3]";  
?>  

Output:

animals are: dog, cat, donkey, monkey

2. Associative Array:

An associative array is a type of array where each element is assigned a unique key instead of a numeric index. This means that you can access the elements of an associative array using their keys instead of their positions.

There are two ways to define associative array:

1st way:

$salary=array("Ram"=>"550000","Shyam"=>"250000","Rahul"=>"200000");  

Example:

<?php    
$salary=array("Ram "=>"550000","Shyam "=>"250000","Rahul"=>"200000");  
echo "Ram salary: ".$salary["Ram "]."<br/>";  
echo "Shyam salary: ".$salary["Shyam"]."<br/>";  
echo "Rahul salary: ".$salary["Rahul"]."<br/>";  
?>    

Output:

Ram salary: 550000
Shyam salary: 250000
Rahul salary: 200000

2nd way:

$salary["Ram"]="550000";  
$salary["Shyam"]="250000";  
$salary["Rahul"]="200000";  

Example:

<?php    
$salary["Ram"]="550000";  
$salary["Shyam"]="250000";  
$salary["Rahul"]="200000";   
echo "Ram salary: ".$salary["Ram"]."<br/>";  
echo "Shyam salary: ".$salary["Shyam"]."<br/>";  
echo "Rahul salary: ".$salary["Rahul"]."<br/>";  
?>    

Output:

Ram salary: 550000
Shyam salary: 250000
Rahul salary: 200000

3. Multidimensional Arrays:

A multidimensional array is an array that contains one or more arrays as its elements. Each array within the multidimensional array is known as a dimension, and can contain its own set of elements. This allows you to store complex data structures in a single variable.

Example:

<?php
$cars = array (
  array("Volvo",22,18),
  array("BMW",15,13),
  array("Saab",5,2),
  array("Land Rover",17,15)
);
echo $cars[0][0].": In stock: ".$cars[0][1].", sold: ".$cars[0][2].".<br>";
?>