Re: What is a class
| From: | Olexandr Vynnychenko | Date: | Sat, 27 Oct 2001 12:32:17 +0000 |
| Subject: | Re: What is a class | ||
| References: | 1 | Groups: | php.doc php.general php.windows |
| Request: | Send a blank email to phpdoc+get-969338225@lists.php.net to get a copy of this message | ||
Hello Jack,
Saturday, October 27, 2001, 1:51:01 PM, you wrote:
J> Dear all
J> I'm fresh on PHP, there is a question which i don't understand , even i had
J> read the book about PHP.
J> There is a Class and object in PHP, but i don't quite understand what is
J> that for.
J> I had look at some of the Example in PHP.net and i know most of it, but
J> there is a operator :
J> $this->edible = $edible;
J> What is the "$this -> " stand for?
J> Could someone please tell me more???
J> Thx
"$this" is object where the function (which uses "$this") is
declared. Here is an example:
class A
{
var $aaa = "foo";
var $bbb;
function fff()
{
echo $aaa; //$aaa is a local variable
}
function ggg()
{
echo $this->aaa; //$aaa is a member of object of class A
}
function hhh($newval)
{
$aaa = $newval;
}
function iii($newval)
{
$this->aaa = $newval;
}
function jjj()
{
ggg();
}
function kkk()
{
$this->ggg();
}
}
$obj = new A; //creating object (or instance) of class A
echo $obj->aaa; //printing object member variable $aaa
//foo
$obj->fff(); //fff() prints its own local variable $aaa (no value)
//
$obj->ggg(); //ggg() prints object member $aaa
//foo
$obj->hhh("bla"); //hhh() changes local variable's value to "bla"
echo $obj->aaa;
//foo
$obj->iii("bla"); //iii() changes object member's value to "bla"
echo $obj->aaa;
//bla
$obj->jjj(); //jjj() tries to call function ggg() that doesn't exists
//!!!error!!!
$obj->kkk(); //kkk() tries to call object member function ggg()
//bla
--
Best regards,
Olexandr mailto:supaboy@i.com.ua