PHP $GLOBALS

[RedBassett]

Greetings,

I have an issue using the $GLOBALS array in PHP.

<?php
$var =array('bar', 'foo');
foreach ($var as $something) {
    $GLOBALS['var'][] = doSomething($something);
}
?>

I need to use the processed version of $var ($GLOBALS['var']) in an external function, however if I reference the processed version in the main file, I have the original array concated with the processed array.

From my understanding, in the external file $GLOBALS['var'] is only set if I declare it, but in the scope of the main file, $GLOBALS['var'] equals $var, even if I don't assign it.

Is there a way to add needed variables to a globally accessible variable, but only if I do so manually, or would I be better to just create my own global system like below?

<?php
$var =array('bar', 'foo');
foreach ($var as $something) {
    $_myglobalvar['var'][] = doSomething($something);
}

function foobar() {
    global $_myglobalvar;
}
?>

- RedBassett

[Charles Stover]

If you still need $var to be equal to Array('bar', 'foo'), then you need a separate variable name. One variable can't equal two values.

If you don't need bar and foo, then do:
foreach ($var as $key => $value)
$var[$key] = doSoemthing($value);

Then access $var from within a function via global $var;

[RedBassett]

Apr 7, 2012 13:57:08 GMT -8 Charles Stover said:

If you still need $var to be equal to Array('bar', 'foo'), then you need a separate variable name. One variable can't equal two values.

If you don't need bar and foo, then do:
foreach ($var as $key => $value)
$var[$key] = doSoemthing($value);

Then access $var from within a function via global $var;

Essentially what I posted in the second part, right? I converted the code to that format on a different git branch, and it seems to be working fine.

- RedBassett

[Charles Stover]

Sure. There is essentially need to ever use $GLOBALS that I can think of.
global $the_var_name does the job, and it rids the confusion you seem to be running into that $GLOBALS['var'] and $var are somehow different (or that appending data to the $GLOBALS['var'] array doesn't also append it to $var).

[RedBassett]

Apr 7, 2012 21:29:56 GMT -8 Charles Stover said:

Sure. There is essentially need to ever use $GLOBALS that I can think of.
global $the_var_name does the job, and it rids the confusion you seem to be running into that $GLOBALS['var'] and $var are somehow different (or that appending data to the $GLOBALS['var'] array doesn't also append it to $var).

The reason I didn't want to use the keyword is because I have multiple global variables, such as my DB connection, my user's data, etc. I realized I could solve this by do $_customGlobalVar['conn'] and $_customGlobalVar['user'], instead of $GLOBALS['conn'] and $GLOBALS['user'].

What confused me about $GLOBALS is the fact that it is different depending on where you call it.

Thanks for the input!

[Charles Stover]

You can make multiple variables global.

global $conn, $user;

[RedBassett]

Apr 9, 2012 10:42:13 GMT -8 Charles Stover said:

You can make multiple variables global.

global $conn, $user;

Yes, but I wanted to avoid this, hence why I was trying to use the $GLOBALS before. Especially in this case, I have easily ten variables needed in a large number of functions.

Too much copy/paste or typing, and then I'd have to update them all if the structure changed.

- RedBassett

[Charles Stover]

Then why not just use $GLOBALS['var'] within the function, without porting them all to a separate variable?

[RedBassett]

Apr 9, 2012 13:10:49 GMT -8 Charles Stover said:

Then why not just use $GLOBALS['var'] within the function, without porting them all to a separate variable?

The $GLOBALS changes depending on the scope it seems, and it was just causing scope issues where a line of code would work differently in different locations. While one more variable, having a custom global var allows me a lot more control over what the code is doing.

Are there major disadvantages (speed, memory, etc) to a custom variable, or or just the writing of a different name?

- RedBassett

[Tylr]

Apr 9, 2012 19:18:21 GMT -8 RedBassett said:

The $GLOBALS changes depending on the scope it seems, and it was just causing scope issues where a line of code would work differently in different locations. While one more variable, having a custom global var allows me a lot more control over what the code is doing.

It sounds like you answered your own question, mate. I don't see a any major disadvantages to using your own custom global variable.

[Charles Stover]

Are there major disadvantages (speed, memory, etc) to a custom variable, or or just the writing of a different name?

Slightly more RAM use, but that's such a level of micro-optimization you don't need to be worried about at all.

[RedBassett]

Apr 10, 2012 6:03:32 GMT -8 Tylr said:

Apr 9, 2012 19:18:21 GMT -8 RedBassett said:

The $GLOBALS changes depending on the scope it seems, and it was just causing scope issues where a line of code would work differently in different locations. While one more variable, having a custom global var allows me a lot more control over what the code is doing.

It sounds like you answered your own question, mate. I don't see a any major disadvantages to using your own custom global variable.

Yeah, in the process of the thread, I started figuring out how $GLOBALS was working.

Apr 10, 2012 12:24:49 GMT -8 Charles Stover said:

Are there major disadvantages (speed, memory, etc) to a custom variable, or or just the writing of a different name?

Slightly more RAM use, but that's such a level of micro-optimization you don't need to be worried about at all.

Not ready to micro optimize yet

Thanks!

- RedBassett