Use array_search( )
.
It returns the key of the found element or false
:
$position = array_search($value, $array); if ($position !== false) { // the element in position $position has $value as its value in array $array }
Use in_array( )
to find if an array contains a value; use
array_search( )
to discover where that value is
located. However, because array_search( )
gracefully handles searches in which the value isn’t
found, it’s better to use array_search( )
instead of in_array( )
. The speed
difference is minute, and the extra information is potentially
useful:
$favorite_foods = array(1 => 'artichokes', 'bread', 'cauliflower', 'deviled eggs'); $food = 'cauliflower'; $position = array_search($food, $favorite_foods); if ($position !== false) { echo "My #$position favorite food is $food"; } else { echo "Blech! I hate $food!"; }
Use the
!==
check against
false
because if your string is found in the array
at position 0
, the if
evaluates
to a logical false
, which isn’t
what is meant or wanted.
If a value is in the array multiple times,
array_search()
is only guaranteed to return one of
the instances, not the first instance.
Recipe 4.12 for checking whether an element
is in an array; documentation on array_search( )
at http://www.php.net/array-search; for more
sophisticated searching of arrays using regular expression, see
preg_replace( )
at
http://www.php.net/preg-replace and Chapter 13.
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