Compare two version strings in PHP

Question

How to compare two strings in version format? such that:

version_compare(\"2.5.1\",  \"2.5.2\") => -1 (smaller)
version_compare(\"2.5.2\",  \"2.5.2\") =&         


        

Answer 1

From the PHP interactive prompt using the version_compare function, built in to PHP since 4.1:

php > print_r(version_compare("2.5.1",  "2.5.2")); // expect -1
-1
php > print_r(version_compare("2.5.2",  "2.5.2")); // expect 0
0
php > print_r(version_compare("2.5.5",  "2.5.2")); // expect 1
1
php > print_r(version_compare("2.5.11", "2.5.2")); // expect 1
1

It seems PHP already works as you expect. If you are encountering different behavior, perhaps you should specify this.