PHP | CachingIterator rewind() Function

The CachingIterator::rewind() function is an inbuilt function in PHP which is used to rewind the iterator.

Syntax:

void CachingIterator::rewind( void )

Parameters: This function does not accept any parameters.

Return Value: This function does not return any value.

Below programs illustrate the CachingIterator::rewind() function in PHP:

Program 1:

<?php

// Declare an ArrayIterator
$arr = new ArrayIterator(
    array(
        "a" => 4,
        "b" => 2,
        "g" => 8,
        "d" => 6,
        "e" => 1,
        "f" => 9
    )
);

// Create a new CachingIterator
$cachIt = new CachingIterator(
    new ArrayIterator($arr),
    CachingIterator::FULL_CACHE
);

// Move to last position
$cachIt->seek(5);

// Display the next value
var_dump($cachIt->next());

// Move to start position
$cachIt->rewind();

// Display the current element
echo $cachIt->current();

?>

Output:

NULL
4

Program 2:

<?php

// Declare an ArrayIterator
$arr = new ArrayIterator(
    array(
        "b" => "for",
        "a" => "Geeks",
        "e" => "Science",
        "c" => "Geeks",
        "f" => "Portal",
        "d" => "Computer"
    )
);

// Create a new CachingIterator
$cachIt = new CachingIterator(
    new ArrayIterator($arr),
    CachingIterator::FULL_CACHE
);

// Check the validity of ArrayIterator
while($cachIt->valid()) {
    $cachIt->next();
}

// Move to start position
$cachIt->rewind();

// Display the current element
echo $cachIt->current();

?>

Output:

for

Reference: https://www.php.net/manual/en/cachingiterator.rewind.php