Question

How to define and use class properties in PHP

Answer 1

class Test 
{
    public $pr = "Class property";
}

$obj = new Test();

echo $obj->pr;

echo "<br />";

var_dump($obj);
 
/*
run:

Class property
object(Test)#1 (1) { ["pr"]=> string(14) "Class property" } 

*/

 

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Answer 2

class Test 
{
    public $pr = "Class property";
  
    public function setProperty($val)
    {
        $this->pr = $val;
    }
  
    public function getProperty()
    {
        return $this->pr;
    }
}
 
$obj = new Test();
 
echo $obj->getProperty(); 
 
echo "<br />";
  
$obj->setProperty("New property value"); 
  
echo $obj->getProperty(); 

echo "<br />";

var_dump($obj);
  
/*
run:
 
Class property
New property value
object(Test)#1 (1) { ["pr"]=> string(18) "New property value" } 
 
*/

 

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Answer 3

class Test 
{
    public $pr = "Class property";
  
    public function setProperty($val)
    {
        $this->pr = $val;
    }
  
    public function getProperty()
    {
        return $this->pr;
    }
}
 
$obj1 = new Test;
$obj2 = new Test;
 
echo $obj1->getProperty();
echo "<br />";
echo $obj2->getProperty();
 
$obj1->setProperty("New property value - first instance");
$obj2->setProperty("New property value - second instance");
 
echo "<br />";
echo $obj1->getProperty();
echo "<br />";
echo $obj2->getProperty();
  
/*
run:
 
Class property
Class property
New property value - first instance
New property value - second instance 
 
*/

 

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