(PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)
version_compare — Compares two "PHP-standardized" version number strings
version_compare() compares two "PHP-standardized" version number strings.
The function first replaces _
, -
and
+
with a dot .
in the version
strings and also inserts dots .
before and after any
non number so that for example '4.3.2RC1' becomes '4.3.2.RC.1'. Then it
compares the parts starting from left to right. If a part contains
special version strings these are handled in the following order:
any string not found in this list
<
dev
< alpha
=
a
< beta
=
b
< RC
=
rc
< #
<
pl
= p
. This way not only versions
with different levels like '4.1' and '4.1.2' can be compared but also any
PHP specific version containing development state.
version1
First version number.
version2
Second version number.
operator
An optional operator. The possible operators
are: <
, lt
,
<=
, le
, >
,
gt
, >=
, ge
,
==
, =
, eq
,
!=
, <>
, ne
respectively.
This parameter is case-sensitive, values should be lowercase.
By default, version_compare() returns
-1
if the first version is lower than the second,
0
if they are equal, and
1
if the second is lower.
When using the optional operator
argument, the
function will return true
if the relationship is the one specified
by the operator, false
otherwise.
The examples below use the PHP_VERSION
constant,
because it contains the value of the PHP version that is executing
the code.
Example #1 version_compare() examples
<?php
if (version_compare(PHP_VERSION, '7.0.0') >= 0) {
echo 'I am at least PHP version 7.0.0, my version: ' . PHP_VERSION . "\n";
}
if (version_compare(PHP_VERSION, '5.3.0') >= 0) {
echo 'I am at least PHP version 5.3.0, my version: ' . PHP_VERSION . "\n";
}
if (version_compare(PHP_VERSION, '5.0.0', '>=')) {
echo 'I am at least PHP version 5.0.0, my version: ' . PHP_VERSION . "\n";
}
if (version_compare(PHP_VERSION, '5.0.0', '<')) {
echo 'I am still PHP 4, my version: ' . PHP_VERSION . "\n";
}
?>
Note:
The
PHP_VERSION
constant holds current PHP version.
Note:
Note that pre-release versions, such as 5.3.0-dev, are considered lower than their final release counterparts (like 5.3.0).
Note:
Special version strings such as
alpha
andbeta
are case sensitive. Version strings from arbitrary sources that do not adhere to the PHP standard may need to be lowercased via strtolower() before calling version_compare().