Foreach value in array php

PHP foreach Loop

The foreach loop - Loops through a block of code for each element in an array.

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PHP foreach Loop
The PHP foreach Loop
Unpacking nested arrays with list()
How can we store values from foreach loop into an array in PHP?
How do you use key value in foreach?
How do I loop through an array of objects in PHP?
What is foreach of array in PHP?

The PHP foreach Loop

The foreach loop works only on arrays, and is used to loop through each key/value pair in an array.

Syntax

foreach ($array as$value) {
code to be executed;
}

For every loop iteration, the value of the current array element is assigned to $value and the array pointer is moved by one, until it reaches the last array element.

Examples

The following example will output the values of the given array ($colors):

Example

<?php
$colors = array("red", "green", "blue", "yellow");

foreach ($colors as $value) {
echo "$value <br>";
}
?>

Try it Yourself »

The following example will output both the keys and the values of the given array ($age):

Example

<?php
$age = array("Peter"=>"35", "Ben"=>"37", "Joe"=>"43");

foreach($age as $x => $val) {
echo "$x = $val<br>";
}
?>

Try it Yourself »

You will learn more about arrays in the PHP Arrays chapter.

(PHP 4, PHP 5, PHP 7, PHP 8)

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. There are two syntaxes:

foreach (iterable_expression as $value)
    statement
foreach (iterable_expression as $key => $value)
    statement

The first form traverses the iterable given by iterable_expression. On each iteration, the value of the current element is assigned to $value.

The second form will additionally assign the current element's key to the $key variable on each iteration.

Note that foreach does not modify the internal array pointer, which is used by functions such as current() and key().

It is possible to customize object iteration.

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

<?php $arr = array(1, 2, 3, 4); foreach ($arr as &$value) { $value = $value * 2; } // $arr is now array(2, 4, 6, 8) unset($value); // break the reference with the last element ?>

Warning

Reference of a $value and the last array element remain even after the foreach loop. It is recommended to destroy it by unset(). Otherwise you will experience the following behavior:

<?php $arr = array(1, 2, 3, 4); foreach ($arr as &$value) { $value = $value * 2; } // $arr is now array(2, 4, 6, 8)

// without an unset($value), $value is still a reference to the last item: $arr[3]

foreach ($arr as $key => $value) {
    // $arr[3] will be updated with each value from $arr...
    echo "{$key} => {$value} ";
    print_r($arr);
}
// ...until ultimately the second-to-last value is copied onto the last value// output:
// 0 => 2 Array ( [0] => 2, [1] => 4, [2] => 6, [3] => 2 )
// 1 => 4 Array ( [0] => 2, [1] => 4, [2] => 6, [3] => 4 )
// 2 => 6 Array ( [0] => 2, [1] => 4, [2] => 6, [3] => 6 )
// 3 => 6 Array ( [0] => 2, [1] => 4, [2] => 6, [3] => 6 )?>

It is possible to iterate a constant array's value by reference:

<?php foreach (array(1, 2, 3, 4) as &$value) { $value = $value * 2; } ?>

Note:
foreach does not support the ability to suppress error messages using @.

Some more examples to demonstrate usage:

<?php /* foreach example 1: value only */$a = array(1, 2, 3, 17);

foreach (

$a as $v) {
    echo "Current value of \$a: $v.\n";
}/* foreach example 2: value (with its manual access notation printed for illustration) */$a = array(1, 2, 3, 17);$i = 0; /* for illustrative purposes only */foreach ($a as $v) {
    echo "\$a[$i] => $v.\n";
    $i++;
}/* foreach example 3: key and value */$a = array(
    "one" => 1,
    "two" => 2,
    "three" => 3,
    "seventeen" => 17
);foreach ($a as $k => $v) {
    echo "\$a[$k] => $v.\n";
}/* foreach example 4: multi-dimensional arrays */
$a = array();
$a[0][0] = "a";
$a[0][1] = "b";
$a[1][0] = "y";
$a[1][1] = "z";foreach ($a as $v1) {
    foreach ($v1 as $v2) {
        echo "$v2\n";
    }
}/* foreach example 5: dynamic arrays */foreach (array(1, 2, 3, 4, 5) as $v) {
    echo "$v\n";
}
?>

Unpacking nested arrays with list()

(PHP 5 >= 5.5.0, PHP 7, PHP 8)

It is possible to iterate over an array of arrays and unpack the nested array into loop variables by providing a list() as the value.

For example:

<?php $array = [ [1, 2], [3, 4], ];

foreach (

$array as list($a, $b)) {
    // $a contains the first element of the nested array,
    // and $b contains the second element.
    echo "A: $a; B: $b\n";
}
?>

The above example will output:

You can provide fewer elements in the list() than there are in the nested array, in which case the leftover array values will be ignored:

<?php $array = [ [1, 2], [3, 4], ];

foreach (

$array as list($a)) {
    // Note that there is no $b here.
    echo "$a\n";
}
?>

The above example will output:

A notice will be generated if there aren't enough array elements to fill the list():

<?php $array = [ [1, 2], [3, 4], ];

foreach (

$array as list($a, $b, $c)) {
    echo "A: $a; B: $b; C: $c\n";
}
?>

The above example will output:

Notice: Undefined offset: 2 in example.php on line 7
A: 1; B: 2; C: 

Notice: Undefined offset: 2 in example.php on line 7
A: 3; B: 4; C:

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How can we store values from foreach loop into an array in PHP?

Your answer Declare the $items array outside the loop and use $items[] to add items to the array: $items = array(); foreach($group_membership as $username) { $items[] = $username; } print_r($items); Hope it helps!!

How do you use key value in foreach?

The foreach looping is the best way to access each key/value pair from an array. array_expr is an array. In every loop the value of the current element of the array is assigned to $value and the internal array pointer is advanced by one and the process continue to reach the last array element. array_expr is an array.

How do I loop through an array of objects in PHP?

PHP provides a way for objects to be defined so it is possible to iterate through a list of items, with, for example a foreach statement. By default, all visible properties will be used for the iteration. echo "\n"; $class->iterateVisible();

What is foreach of array in PHP?

The foreach loop is used to traverse the array elements. It works only on array and object. It will issue an error if you try to use it with the variables of different datatype. The foreach loop works on elements basis rather than index. It provides an easiest way to iterate the elements of an array.