classes and functions

[Slyverson]

For some reason, when I try to create a class variable, it does not carry forward to the other functions.

//class
class foo
{
function foo($var1)
{
$this->foovar = $var1;
}

function printfoo()
{
	echo $this->foovar;
}

}

//call from page

include("classpage.php")
$cart = new foo($var1);
$cart->printfoo();

When I try to echo $this->foovar in either class function, I get nothing. If I try to echo the $var1 within the foo function, it comes through.

Am I just being slow here? Have I been at it too many hours???? Any suggestions would be appreciated.

[swr]

Usually you should declare the variable..

class foo {
var $var1;
// etc
}

That might be the problem.

[Slyverson]

I tried that. It still isn't passing the variable to the second function.

Every documentation I look at shows me to do it exactly how i am doing it.

I appreciate your time.

Cheers.

[swr]

I just tried the code that you posted, and it works fine, even without declaring the member variable.

Are you maybe doing something else? I wonder if you're not being bitten by the "copy on assignment" thing...

$x = new foo("aaa");
$y = $x; // $y is a clone, not the same instance!
$x->foovar = "bbb";
$y->printfoo(); // prints aaa

It can also get you with some language constructs, like foreach:

$a = new foo("aaa");
$b = new foo("bbb");
$c = new foo("ccc");
$objects = array($a, $b, $c);
foreach ($objects as $o) {
    $o->foovar = "ddd";
    $o->printfoo(); // prints "ddd"
}
foreach ($objects as $o) {
    $o->printfoo(); // prints "aaa", "bbb", "ccc"
}

The solution is to always assign objects by reference (=& instead of =), and don't use foreach like that.