version_compare
(PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)
version_compare — Compares two "PHP-standardized" version number strings
Description
$version1, string $version2, ?string $operator = null): int|boolversion_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.
Parameters
-
version1 -
First version number.
-
version2 -
Second version number.
-
operator -
An optional operator. The possible operators are:
<,lt,<=,le,>,gt,>=,ge,==,=,eq,!=,<>,nerespectively.This parameter is case-sensitive, values should be lowercase.
Return Values
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.
Examples
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";
}
?>
Notes
Note:
The
PHP_VERSIONconstant 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
alphaandbetaare 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().
See Also
- phpversion() - Gets the current PHP version
- php_uname() - Returns information about the operating system PHP is running on
- function_exists() - Return true if the given function has been defined
