ZEND PHP 5 Certification STUDY GUIDE

Functions ” 41
$a = "Hello";
$b = "World";
function hello()
{
echo $GLOBALS[’a’] .’ ’. $GLOBALS[’b’];
}
hello(); // Displays "Hello World"
Passing Arguments
Arguments allow you to inject an arbitrary number of values into a function in order
to influence its behaviour:
function hello($who)
{
echo "Hello $who";
}
hello("World");
/* Here we pass in the value, "World", and the function displays "Hello World"
*/
You can define any number of arguments and, in fact, you can pass an arbitrary number
of arguments to a function, regardless of how many you specified in its declaration.
PHP will not complain unless you provide fewer arguments than you declared.
Additionally, you can make arguments optional by giving them a default value.
Optional arguments must be right-most in the list and can only take simple values—expressions
are not allowed:
Licensed to 482634 - Amber Barrow (itsadmin@deakin.edu.au)
function hello($who = "World")
{
echo "Hello $who";
}
hello();
/* This time we pass in no argument and $who is assigned "World" by default. */