Description
array
array_filter ( array input [,
callback function])
array_filter() returns an array
containing all the elements of
input filtered according a callback function. If the input is an associative array the
keys are preserved.
範例 1. array_filter()
example
function odd($var) {
return ($var % 2 == 1);
}
function even($var) {
return ($var % 2 == 0);
}
$array1 = array ("a"= 1, "b"= 2, "c"= 3, "d"= 4, "e"= 5);
$array2 = array (6, 7, 8, 9, 10, 11, 12);
echo "Odd :\n";
print_r(array_filter($array1, "odd"));
echo "Even:\n";
print_r(array_filter($array2, "even"));
|
The printout of the program above will be:
Odd :
Array
(
[a] = 1
[c] = 3
[e] = 5
)
Even:
Array
(
[0] = 6
[2] = 8
[4] = 10
[6] = 12
)
|
|
Users may not change the array itself from the callback
function. e.g. Add/delete an element, unset the array that array_filter() is applied to. If the
array is changed, the behavior of this function is
undefined.
See also array_map() and
array_reduce().