PHP | ArrayIterator key() Function
Last Updated :
21 Nov, 2019
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The ArrayIterator::key() function is an inbuilt function in PHP which returns the current key of the array element.
Syntax:
php
php
mixed ArrayIterator::key( void )Parameters: This function does not accept any parameters. Return Value: This function returns the current array key. Below programs illustrate the ArrayIterator::key() function in PHP: Program 1:
<?php
// Declare an ArrayIterator
$arrItr = new ArrayIterator(
array('G', 'e', 'e', 'k', 's', 'f', 'o', 'r')
);
// Loop to display the array iterator key
foreach($arrItr as $element) {
echo $arrItr->key() . "\n";
}
?>
<?php // Declare an ArrayIterator$arrItr = new ArrayIterator( array('G', 'e', 'e', 'k', 's', 'f', 'o', 'r'));// Loop to display the array iterator keyforeach($arrItr as $element) { echo $arrItr->key() . "\n";} ?>
Output:
Program 2:
0 1 2 3 4 5 6 7
<?php
// Declare an ArrayIterator
$arrItr = new ArrayIterator(
array(
"a" => "Geeks",
"b" => "for",
"c" => "Geeks"
)
);
// Append the element into array iterator
$arrItr->append("Computer");
$arrItr->append("Science");
$arrItr->append("Portal");
// Display the key and its value of
// array iterator
foreach($arrItr as $element) {
echo "key: " . $arrItr->key() . " Value: "
. $arrItr->current() . "\n";
}
?>
<?php // Declare an ArrayIterator$arrItr = new ArrayIterator( array( "a" => "Geeks", "b" => "for", "c" => "Geeks" )); // Append the element into array iterator$arrItr->append("Computer");$arrItr->append("Science");$arrItr->append("Portal");// Display the key and its value of// array iteratorforeach($arrItr as $element) { echo "key: " . $arrItr->key() . " Value: " . $arrItr->current() . "\n";}?>
Output:
Reference: https://www.php.net/manual/en/arrayiterator.key.php
key: a Value: Geeks key: b Value: for key: c Value: Geeks key: 0 Value: Computer key: 1 Value: Science key: 2 Value: Portal
