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Posted by Jochem Maas on 04/22/05 21:21
Richard Davey wrote:
> Hello Satyam,
>
> Friday, April 22, 2005, 3:59:38 PM, you wrote:
>
> S> I've been going through the manual and haven't found 'var'
> S> documented anywhere, as far as I found, it is just used, and that's
> S> it. It seems it first appears when it talks about Classes, and it
> S> is just used in the examples as if everyone knew what var is
> S> supposed to do.
>
> It's a "constant initializer" - which is both an accurate and
> misleading title at the same time :) It will initialise a variable to
> be constant through-out your entire class (meaning any method can
> access it) but unlike true PHP constants (those created with define)
> the value of the variable can be manipulated from just about anywhere.
indeed in php you can do the following instead:
<?
error_reporting( E_ALL & E_STRICT );
class Test
{
// this first var (commented out) should (I thought) act as if defined
// 'public' - it doesn't given a parse error with php -l, but does when run.
// I haven't run into this problem in 1.5 years of writing php5...
// I must be having a brain freeze :-/
//$myVar;
// publically accessible instances variables
public $myVar1; // not initialized with a value
public $myVar2 = "2"; // initialized with a value
// an instance variable thats only available
// from within _all_ methods of this object.
// .. methods could be defined in subclasses or parent-classes
protected $myVar3 = "3";
// an instance variable that is only available to the
// methods defined in _this_ class
private $myVar4 = "4";
// a variable with class scope (all instances see the same value),
// publically accessible
static $myVar5 = "5";
static public $myVar6 = "6";
// a variable with class scope (all instances see the same value),
// thats only available from within _all_ methods of this object.
static protected $myVar7 = "7";
// a variable with class scope (all instances see the same value),
// thats only available from methods defined in _this_ class
static private $myVar8 = "8";
public function get4() { return $this->myVar4; }
public function get8() { return self::$myVar8; }
}
// basic usage examples:
var_dump( ($t = new Test), $t->myVar2, $t->get4(), Test::$myVar6, $t->get8() );
?>
I can thoroughly recommend php5's much improved object model,
try other variations of calls to the defined 'myVar's, also try doing
with sublcasses, see what does/doesn't work, have fun :-)
>
> It is of course PHP4 only and is depreciated in PHP5.
>
> Best regards,
>
> Richard Davey
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