Is it possible to switch in PHP based on version?

Question

I have a function in one of my PHP scripts that relies on version 5.3 to run.

I thought that if it was in a function that didn\'t happen to get called when run on a serv

Answer 1

There are numerous ways to solve this. I prefer detecting the version and executing function.

1. There is a function called phpversion() or constant PHP_VERSION that gives you the current php version

   Use them like

   if(phpversion() == '5.3') {
     //specific php functions
   }
   

2. To check if the current version is newer or equal to lets say '5.3.2'. simply use:

   if (strnatcmp(phpversion(),'5.3.2') >= 0) {
       # equal or newer
   }
   else {
      # not 
   }
   

3. Or, use version_compare to know

   if (version_compare(PHP_VERSION, '5.3.0') >= 0) {
       echo 'I am at least PHP version 5.3.0, my version: ' . PHP_VERSION . "\n";
   }
   

Or ever more user friendly version is to use function_exists()

if (!function_exists('function_name')) {
    // the PHP version is not sufficient
}

Answer 2

Have a separate code file with your PHP 5.3+ code, and only include() it if you detect 5.3 or greater.

Answer 3

You might look at implementing PHP 5.3+ functions if they don't exist.

if (!function_exists('array_replace')) {
    function array_replace(....) {
        // logic here
    }
}

If you have to detect the version, you can use PHP_VERSION.

Answer 4

Have a look at the PHP predefined constants. They include several constants that define the running version. You could use that to decide which version of a script to load.