I face a strange problem including php files. Let me show you the code:
// constants.php
$MYSQL_HOST_PORT = 'localhost:3306';
// functions.php
include 'constants.php';
function getVar() {
echo $MYSQL_HOST_PORT;
}
// doSth.php
include 'functions.php';
echo $MYSQL_HOST_PORT; // The variable is visible and echoed normally as expected!
echo getVar(); // The variable is not echoed! its "".
Any ideas ?
For one, the echo in echo getVar(); won't ever print anything, because getVar doesn't return a value.
Secondly, if you (for some reason) want getVar() itself to work correctly, you need to add a global $MYSQL_HOST_PORT; line, to make it look for $MYSQL_HOST_PORT in the global scope.
getVar() to actually echo something besides an unset variable, running echo getVar() would still result in something being echo'd though the function name is misleading.
echo getVar() would echo something, but that specific echo wouldn't be causing any output.
return $MYSQL_HOST_PORT the problem will still remain.$MYSQL_HOST_PORT in the global scope. Normally, a function will only "see" variables that are declared in its own local scope, so as far as getVar() is concerned, $MYSQL_HOST_PORT doesn't exist. One way around this is to add a global declaration for that variable inside the function, so PHP will look for it in the global scope. (Avoiding the global variable entirely would probably be preferable, though).Rather than globalising the $MYSQL_HOST_PORT variable, why not simply make it a constant?
// constants.php
define('MYSQL_HOST_PORT', 'localhost:3306');
Provided constants.php is included, you can reference the MYSQL_HOST_PORT constant anywhere.
As indicated in zerocrate's answer, the issue is a scoping one. The enclosed scope of the getVar() function does not include $MYSQL_HOST_PORT.
One thing that I can see wrong is that with the line echo getVar(); you are not getting a return value from the function so you can simply write getVar(); by itself.
$MYSQL_HOST_PORT variable is not in scope of the getVar() function so it's not ever going to work as-is.