question about globals

sfullman

Hi There,

OK, try and absorb what I'm doing at face value before you tell me I'm on the wrong track.

I have form that has fields named schemaArray[1][2], where 1 and 2 could be other numbers (it's a 2d array).

sometimes I get schemaArray into a "local" array from a database. Sometimes it comes in from a form, which you could refer to by $_POST['schemaArray'][1][2].

Lets' supppose I have a form submission with a bunch of schemaArray posts. I want to selectively "unset", say $_POST['schemaArray'][2][5] (we'll just say column 2, row 5).

In the function I declare global $_POST; so far so good. If I were to look at all of my form post ...[2][5] would be missing. But now I want to see if there's something in $schemaArray[2][5], i.e. my LOCAL array I got from the database. So I declare global $schemaArray;

What happens it looks like is that PHP goes back to the $POST['schemaArray'] collection, and considers it as $schemaArray. So, in effect, I never really got rid of $POST['schemaArray'][2][5], it's back to irritate me.

does anyone have any suggestions, on how to have a "local" array, a "post" array of the same name, selectively unset parts of the post and then be able to ask if the local parts are there but the post is not, FROM WITHIN A FUNCTION?

Thanks,
Sam Fullman

diego25

Ok, first of all, $POST is a superglobal, so you don't need to say "global $POST" inside a function. Also, if $schemaArray is local to the function, you don't need to say "global $schemaArray" either.

Diego

sfullman

problem is, schema array is "local" to the script but not to the function. By local I mean it's a variable I declare or include, vs. something that comes via POST or GET or COOKIES or SESSION.

Think of it as a chess board, 2 dimensional. $_POST[schemaArray][x][y] is the chessboard on start, but I also declare $schemaArray[x1][y1] and $schemaArray[x2][x2] on the script.

I want to unset POST[schemaArray], let's say partially. I can do that from outside the function. But, to compare POST[schemaArray] with $schemaArray, I need to declare $schemaArray as global so I can see it.

Then, what happens is that PHP gets the value of $_POST[schemaArray][x][y], whether I "unset" it or not, and considers that as the value of say $schemaArray[x][y] as long as $schemaArray[x][y] was not already set/declared. This causes misleading results.

I hope that makes sense. I want some way to NOT have this happen when I declare schemaArray as global.

There's a lot of discussions on the boards about globals and on php.net, now I see why.

Sam Fullman
Compass Point Media

diego25

I tried to figure out what you were saying with this program:

<?
$_POST['schemaArray'][0][0] = 'a';
$schemaArray[1][1] = 'b';

function func() {
	global $schemaArray;
	unset($_POST['schemaArray'][0][0]);

}

func();

print $schemaArray[0][0];
print $_POST['schemaArray'][0][0];

?>

But it outputs "undefined index 0" for both the print statements, which is correct. So none of the behaviour that you mentioned happened. Could you post a sample program (i.e. a short program, not your actual entire program) that demonstrates the behaviour you're talking about?

Diego