The ArrayIterator::offsetExists() function is an inbuilt function in PHP which is used to check the existence of offset at the given index.
Syntax:
bool ArrayIterator::offsetExists( mixed $index )
Parameters: This function accepts single parameter $index which holds the index value to check the existence of offset.
Return Value: This function returns TRUE if the offset exists, otherwise returns FALSE.
Below programs illustrate the ArrayIterator::offsetExists() function in PHP:
Program 1:
<?php // Declare an ArrayIterator $arrItr = new ArrayIterator(
array (
"a" => 4,
"b" => 2,
"g" => 8,
"d" => 6,
"e" => 1,
"f" => 9
)
); // Display the offset value var_dump( $arrItr ->offsetGet( "a" ));
// Check the existence of offset var_dump( $arrItr ->offsetExists( "a" ));
// Unset the offset value var_dump( $arrItr ->offsetUnset( "a" ));
// Check the existence of offset var_dump( $arrItr ->offsetExists( "a" ));
?> |
Output:
int(4) bool(true) NULL bool(false)
Program 2:
<?php // Declare an ArrayIterator $arrItr = new ArrayIterator(
array (
"for" , "Geeks" , "Science" ,
"Geeks" , "Portal" , "Computer"
)
); // Print the value at index 1 echo $arrItr ->offsetGet(1) . "\n" ;
// Check the existence of offset var_dump( $arrItr ->offsetExists(1));
// Unset the offset value var_dump( $arrItr ->offsetUnset(1));
// Check the existence of offset var_dump( $arrItr ->offsetExists(1));
// Print the value at index 0 echo $arrItr ->offsetGet(0) . "\n" ;
// Check the existence of offset var_dump( $arrItr ->offsetExists(0));
// Unset the offset value var_dump( $arrItr ->offsetUnset(0));
// Check the existence of offset var_dump( $arrItr ->offsetExists(0));
?> |
Output:
Geeks bool(true) NULL bool(false) for bool(true) NULL bool(false)
Reference: https://www.php.net/manual/en/arrayiterator.offsetexists.php