(PHP 4, PHP 5, PHP 7)
array_flip — Exchanges all keys with their associated values in an array
$array
) : array
array_flip() returns an array in flip
order, i.e. keys from array
become values and values
from array
become keys.
Note that the values of array
need to be valid
keys, i.e. they need to be either integer or
string. A warning will be emitted if a value has the wrong
type, and the key/value pair in question will not be included
in the result.
If a value has several occurrences, the latest key will be used as its value, and all others will be lost.
array
An array of key/value pairs to be flipped.
Returns the flipped array on success and NULL
on failure.
Example #1 array_flip() example
<?php
$input = array("oranges", "apples", "pears");
$flipped = array_flip($input);
print_r($flipped);
?>
The above example will output:
Array ( [oranges] => 0 [apples] => 1 [pears] => 2 )
Example #2 array_flip() example : collision
<?php
$input = array("a" => 1, "b" => 1, "c" => 2);
$flipped = array_flip($input);
print_r($flipped);
?>
The above example will output:
Array ( [1] => b [2] => c )