Classes and Confusion

[Sinzygy]

Ok, I'm working on something and I wrote the following code:

Code: [Select]

class castle
{
function castle($id)
{
global $db;
$sql = "SELECT * FROM castles WHERE castleid = '$id'";

$exclude_vars = array("userid");
$rs = $db->Execute($sql);
$rs = $rs->GetRows();

foreach($rs[0] as $key => $value)
{
if(!in_array($key,$exlucde_vars))
{
$this->$key = $value;
}
}
}
}

And it seems to be working. And this is where I'm confused:

It seems to be working to use new class-variables without declaring them first. I mean, usually I'd write out all the variables I want (var $food, var $gold, etc.) but apparently I don't need to do that. Or is it just my local version of PHP that let's me do it this way.

[Zeggy]

To be honest, I'm not sure of when you need to 'declare' a variable first before you assign a variable to it.
I've noticed that it is required sometimes when I'm working with arrays in classes.

[beam]

When you use:

Code: [Select]

$this->$key = $value

You are declaring them, that is the declaration statement. For example, say $rs[] is this:

Code: [Select]

$rs = array("one" => 1, "two" => 2, "three" => 3);

Now, you're taking that array and declaring the keys of the arrays as class variables. After you exectute that last inner for loop, you'll be able to access the following $this->one, $this->two, and $this->three because you declared them as class variables inside the for loop.

I hope that helps, unless I misunderstood what you were asking.

[Sinzygy]

thanks beam, that was exactly what I was asking.

It was only that I always used to write each variable at the beginning of a class with "var $somevar;". But this saves me a sh*tload of time