Php: the global keyword

Self-tutoring about PHP: the tutor mentions an idea about PHP global.

Consider the file

$var1=”hello”;

function f1(){

echo $var1;

}

f1(); //call f1

In the code above, with almost any programming language I know of, $var1 has value “hello” in the function f1. f1 can override it, but if not, then $var1 maintains its external, “global” value: “hello”.

With the version of PHP I use, however, the $var1 inside f1 is undefined. To make it take on the value of the external $var1, it needs to be declared in f1 as global:

$var1=”hello”;

function f1(){

global $var1;

echo $var1;

}

With the global $var1 declaration, a call to f1 will cause it to output “hello”.

Source:

php.net

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.