CODEWITHSUNDEEP
phpinheritance
Muhammad Hamza Nisar
Muhammad Hamza Nisar

Reputation: 601

Inheritance Class is not working fine in PHP

I created Person class, then extended it to Student class. When I call a method on a Student object, it doesn't work as expected.

Here is my code

class Person{
    static public $IsAlive;
    public $FirstName;
    public $LastName;
    public $Gender;
    public $Age;
    static public $total_person = 1;
    static public $type;

    function __construct($FirstName,$LastName,$Gender,$Age,$IsAlive,$type=""){
        self::$IsAlive = $IsAlive;
        if(self::$IsAlive === TRUE){
            echo "<strong>Person Number#" . self::$total_person++ . "</strong> details are given below: <br />";
            $this->FirstName = $FirstName;
            $this->LastName = $LastName;
            $this->Gender = $Gender;
            $this->Age = $Age;
            self::$type = $type;
        }else{
            echo "This Person is not longer available <br />";
        }
    }
    function PersonDetail(){
        if(self::$IsAlive === TRUE){
            echo "Person Name: " . $this->FirstName . " " . $this->LastName . "<br />";
            echo "Person Gender: " . $this->Gender . "<br />";
            echo "Age: " . $this->Age;
        }
    }

}
class Student extends Person{
    public $standard = "ABC";
    public $subjects = "ABC";
    public $fee = "123";
    function StudentDetail(){
        if(parent::$type === "Student"){
            return parent::PersonDetail();
            echo "Education Standard: " . $this->standard;
            echo "Subjects: " . $this->subjects;
            echo "Fee: " . $this->fee;
            echo parent::$type;
        }
    }
}

$Hamza = new Student("Muhammad Hamza","Nisar","Male","22 years old",TRUE,"Student");
$Hamza->StudentDetail();

It's printing PersonDetail() only, but not printing the complete information like education standard, subjects and fee.

Here is my Output 

Person Number#1 details are given below: 
Person Name: Muhammad Hamza Nisar
Person Gender: Male
Age: 22 years old

I need to see the StudentDetail() output below it as well. What's wrong and how to fix it?

Upvotes: 0

Views: 51

Answers (1)

Yury Fedorov
Yury Fedorov

Reputation: 14938

If you put a return statement inside your function (or method), PHP will not proceed the execution after this point (most of the time)*. So, when the following code (taken from your question) is executed, it stops after you call return parent::PersonDetail();. 

function StudentDetail() {
    if(parent::$type === "Student") {
        return parent::PersonDetail();
        echo "Education Standard: " . $this->standard;
        echo "Subjects: " . $this->subjects;
        echo "Fee: " . $this->fee;
        echo parent::$type;
    }
}

Since PersonDetail() method displays information itself, you don't need to return its value. It is enough just to call it in this case: 

function StudentDetail() {
    if(parent::$type === "Student") {
        parent::PersonDetail(); // this will echo parent output

        // and this code will still be executed
        echo "Education Standard: " . $this->standard;
        echo "Subjects: " . $this->subjects;
        echo "Fee: " . $this->fee;
        echo parent::$type;
    }
}

In case of this question this is irrelevant, but sometimes the execution proceeds even after a function has returned, e.g in finally clause

Upvotes: 3

Related Questions