Passing by Reference
Passing by Reference
You can pass a variable by reference to a function so the function can modify the variable. The syntax is as follows:
<?php function foo(&$var) { $var++; } $a=5; foo($a); // $a is 6 here ?>
Note: There is no reference sign on a function call - only on function definitions. Function definitions alone are enough to correctly pass the argument by reference. As of PHP 5.3.0, you will get a warning saying that "call-time pass-by-reference" is deprecated when you use & in foo(&$a);. And as of PHP 5.4.0, call-time pass-by-reference was removed, so using it will raise a fatal error.
The following things can be passed by reference: