Question

<?php
try{

    $test = new TestAccessModifiers("2345","xyz","vfd","a0001","99","67"); /*invoking the class*/

    var_dump($test->calculate());
}
catch(Exception $e){

    echo $e->getMessage();
}
?>

<?php 
class TestAccessModifiers {


    function TestAccessModifiers($user_p,$user_fn,$user_ln,$user_id,$marks1,$marks2) {
        echo "hello1";
        $this->user_phone=$user_p;
        $this->user_fname=$user_fn;
        $this->user_lname=$user_ln;
        $this->user_id=$user_id;
        $this->marks1=$marks1;
        $this->marks2=$marks2;


        echo $this->marks1;
    }
    private  $additional_marks = 10;
    public static function calculate(){


        return $this->marks1+$this->marks2+$this->getAdditionalmarks();

    }

    public function getAdditionalmarks(){

        return $this->additional_marks;
    }


}
?>

Above is the simple code i am trying to run… but i am unable to call TestAccessModifiers
I have tried using _constructor too

Answer 1

if you are calling the class in another php page, make sure you include it like this.

include('/path/to/your/class.php');
$test = new TestAccessModifiers("2345", "xyz", "vfd", "a0001", "99", "67");

or if you are instantiating the object within the same file then place the instantiation code below your class.

class TestAccessModifiers {
    public function __construct($user_p, $user_fn, $user_ln, $user_id, $marks1, $marks2) {
        echo "hello1";
        $this->user_phone = $user_p;
        $this->user_fname = $user_fn;
        $this->user_lname = $user_ln;
        $this->user_id = $user_id;
        $this->marks1 = $marks1;
        $this->marks2 = $marks2;
        echo $this->marks1;
    }
    private $additional_marks = 10;

    public function calculate() {
        return $this->marks1 + $this->marks2 + $this->getAdditionalmarks();
    }
    public function getAdditionalmarks() {
        return $this->additional_marks;
    }
}

try {
    $test = new TestAccessModifiers("2345", "xyz", "vfd", "a0001", "99", "67"); /*invoking the class*/
    var_dump($test->calculate());
} catch (Exception $e) {
    echo $e->getMessage();
}

you have defined a static method in your class, and have used the pseudo variable $this inside of the static method, which PHP does not allow. since static method is treated out of object context in PHP. you need to remove the static method to use $this