How to use php each function

php each function is used to return the key name and key value of the current element and move the internal pointer backward. The syntax is each(array), and the parameter array is required and refers to the array to be used.

#How to use each function in php?

Definition and usage

each() function returns the key name and key value of the current element and moves the internal pointer backward.

The key name and key value of the element are returned to an array with four elements. Two elements (1 and Value) contain the key value, and two elements (0 and Key) contain the key name.

Related methods:

current() - Returns the value of the current element in the array.

end() - Sets the internal pointer to the last element in the array and outputs it.

next() - Sets the internal pointer to the next element in the array and outputs it.

prev() - Sets the internal pointer to the previous element in the array and outputs it.

reset() - Set the internal pointer to the first element in the array and output it.

Tips: each() function is deprecated in PHP 7.2.0.

Syntax

each(array)

Parameters

array Required. Specifies the array to use.

Return value: Returns the key name and key value of the current element. The element's key name and value are returned in an array with four elements. Two elements (1 and Value) contain the key value, and two elements (0 and Key) contain the key name. If there are no more array elements, the function returns FALSE.

PHP Version: 4

Example 1

Same as the one at the top of the page, but this one outputs the entire array via a loop:

<?php
$people = array("Peter", "Joe", "Glenn", "Cleveland");
 
reset($people);
 
while (list($key, $val) = each($people))
{
    echo "$key => $val<br>";
}
?>

Output:

0 => Peter
1 => Joe
2 => Glenn
3 => Cleveland

Example 2

Demonstration of all relevant methods:

<?php
$people = array("Peter", "Joe", "Glenn", "Cleveland");
 
echo current($people) . "<br>"; // The current element is Peter
echo next($people) . "<br>"; // The next element of Peter is Joe
echo current($people) . "<br>"; // Now the current element is Joe
echo prev($people) . "<br>"; // The previous element of Joe is Peter
echo end($people) . "<br>"; // The last element is Cleveland
echo prev($people) . "<br>"; // The previous element of Cleveland is Glenn
echo current($people) . "<br>"; // Now the current element is Glenn
echo reset($people) . "<br>"; // Moves the internal pointer to the first element of the array, which is Peter
echo next($people) . "<br>"; // The next element of Peter is Joe
 
print_r (each($people)); // Returns the key and value of the current element (now Joe), and moves the internal pointer forward
?>

Output:

Peter
Joe
Joe
Peter
Cleveland
Glenn
Glenn
Peter
Joe

Array ( [1] => Joe [value] => Joe [0] => 1 [key] => 1 )

Example 3

Returns the key name and key value of the current element, and moves the internal pointer backward:

<?php
$people = array("Peter", "Joe", "Glenn", "Cleveland");
print_r (each($people));
?>

Output:

Array ( [1] => Peter [value] => Peter [0] => 0 [key] => 0 )

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