Why is the global $ object_name discouraged?

Question

I have two classes, and currently I am referencing one another using this:

ClassB :: func ()
{
    global $ classAObject;
    echo $ classAObject-> whatever ();
}

However, I was told that use is globalnot recommended. This and why?

+3

Bojangles May 02, '11 at 16:29

2 answers

, . :

ClassB::func($classAObject)
{
    echo $classAObject->whatever();
}

0

Neal 02 '11 16:30

Erik · Accepted Answer · 2011-05-02T16:42:12+0000

There are many reasons not to use global variables. Here are just a few:

Region
- On a large system, it can be easy to accidentally reassign global variables if you reuse a semi-common name
- Variables on a global scale increase the memory capacity of your scripts. Not always important, but may be
- - - ,
- . .
- . .

, , - , .

classB::func($obj) 
{
   echo $obj->whatever();
}

$obj = new classAObject;
classB::func($obj);