Description
bool
in_array ( mixed needle, array
haystack [, bool strict])
Searches haystack for
needle and returns TRUE if it is found in the
array, FALSE otherwise.
If the third parameter
strict is set to
TRUE then the in_array()
function will also check the
types of the needle in
the haystack.
注: If needle
is a string, the comparison is done in a case-sensitive
manner.
注: In PHP versions before 4.2.0 needle was not allowed to be an
array.
範例 1. in_array()
example
$os = array ("Mac", "NT", "Irix", "Linux");
if (in_array ("Irix", $os)) {
print "Got Irix";
}
if (in_array ("mac", $os)) {
print "Got mac";
}
|
The second condition fails because in_array() is case-sensitive, so the
program above will display:
|
範例 2. in_array() with
strict example
?php
$a = array('1.10', 12.4, 1.13);
if (in_array('12.4', $a, TRUE))
echo "'12.4' found with strict check\n";
if (in_array(1.13, $a, TRUE))
echo "1.13 found with strict check\n";
?
|
This will display:
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範例 3. in_array() with
an array as needle
?php
$a = array(array('p', 'h'), array('p', 'r'), 'o');
if (in_array(array ('p', 'h'), $a))
echo "'ph' was found\n";
if (in_array(array ('f', 'i'), $a))
echo "'fi' was found\n";
if (in_array('o', $a))
echo "'o' was found\n";
?
// This will output:
'ph' was found
'o' was found
|
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See also array_search().