PHP: Difference between revisions

One advantage of PHP scripts is because they are processed by the web server nobody can steal your script unless you use some functionality like that [https://cumulus.hosiene.co.uk/viewtopic.php?f=14&t=16425&p=126065 described here].

 

 

PHP allows you to use syntax like 'require' or 'include' to effectively bring in common code from other files. Put simply, when the PHP parser finds "require_once 'file_name';", "require 'file_name';", or the alternative include syntax, the parser reads the file referenced and treats it as if it is part of the original file from then onwards. "include" does not cause an error if it cannot find the file requested. "require" creates an error and aborts the main script if it cannot find the named file. The "_once" is used if the file you want to bring in includes setting variables that you later want to give a new value to, because your new value would be lost if the include happened again. Also a function can only be declared once so if script you select to bring in contains one or more function definitions, either that script must check if function has already been declared before it declares it, or that script must be called with the "_once" variant. However, because using "_once" creates a considerable overhead, the parser must read all files currently loaded to see if the named script is referenced anywhere else, it is bad coding to use "require_once"/"include_once" variant if the aforementioned reasons don't make it necessary, instead just use plain "require" or "include".