Table of Contents

Introduction

The foreach construct provides an easy way to iterate over arrays. foreach works only on arrays and objects, and will issue an error when you try to use it on a variable with a different data type or an uninitialized variable.

Syntax of the foreach Loop

The syntax of the foreach loop is given as:

Syntax

The foreach loop.

1foreach ($array as $value) {
2    statement(s);
3}

where

  • $array is the name of the array we want to loop through.
  • $value is a variable name that PHP uses to store the value of the current array item.
Note

In order to be able to directly modify array elements within the loop, precede $value with the & character. In that case the value will be assigned by reference.

An alternative syntax of the foreach loop that works with associative arrays is given as:

Syntax

The foreach loop (alternative syntax).

1foreach ($array as $key => $value) {
2    statement(s);
3}

where, in addition to the $array and $value defined earlier, we have

  • $key is an optional variable name that PHP uses to store the key of the current array item.

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Using the foreach Loop

Example

Using the foreach loop on an array.

1<?php
2    $cars = array("Volvo", "BMW", "Toyota", "Lexus");
3    foreach ($cars as $value) {
4        echo "$value <br>";
5    }
6?>

Volvo
BMW
Toyota
Lexus

To directly modify array elements within the loop, we precede $value with the & character. In the following example, the character X is appended to each item of the array.

Example

Using the foreach loop and modifying an array.

1<?php
2    $cars = array("Volvo", "BMW", "Toyota", "Lexus");
3    foreach ($cars as &$value) {
4        $value .= "X";
5        echo "$value <br>";
6    }
7    print_r($cars); // modified
8?>

VolvoX
BMWX
ToyotaX
LexusX
Array ( [0] => VolvoX [1] => BMWX [2] => ToyotaX [3] => LexusX )

If we did not precede $value with &, the original array will not be modified.

Example

Using the foreach loop on an array without modification.

1<?php
2    $cars = array("Volvo", "BMW", "Toyota", "Lexus");
3    foreach ($cars as $value) {
4        $value .= "X";
5        echo "$value <br>";
6    }
7    print_r($cars); // not modified
8?>

VolvoX
BMWX
ToyotaX
LexusX
Array ( [0] => Volvo [1] => BMW [2] => Toyota [3] => Lexus )

Example

Using the foreach loop on an associative array.

1<?php
2    $age = array("John"=>"36", "Lex"=>"24", "Tim"=>"33", "Julian"=>"28");
3    foreach($age as $item => $val) {
4        echo "$item: $val<br>";
5    }
6?>

John: 36
Lex: 24
Tim: 33
Julian: 28