Level 13
public function __conttruct($firstname, $lastname, $age){
That's not how you spell __construct.
Aug 2, 2017
6
Level 5
OOP Question
In my effort to learn OOP I'm trying to figure this out and maybe someone can help. Yea I know this is basic stuff, but what can I say.
I'm tying to figure out why I get this error Undefined variable: age (line 27) Fatal error: Cannot access empty property on line 27
Code
<!DOCTYPE html>
<html>
<head>
<title>Reconstructing the Person Class</title>
<link type='text/css' rel='stylesheet' href='style.css'/>
</head>
<body>
<p>
<?php
class person {
public $isAlive = true;
public $firstname;
public $lastname;
public $age;
public function __conttruct($firstname, $lastname, $age){
$this->$firstname = $firstname;
$this->$lastname = $lastname;
$this->$age = $age;
}
}
$teacher = new Person("boring", "12345", 12345);
$student = new Person("John", "Doe", 34);
echo $student->$age;
echo $teacher->isAlive;
?>
</p>
</body>
</html>```
So doesn't the constructor pull the values $student variable?
Don't laugh. LOL
Level 8
And you have an extra $ sign on:
echo $student->$age;
should be:
echo $student->age;
Level 5
I dont get the error now but dont get the age
<!DOCTYPE html>
<html>
<head>
<title>Reconstructing the Person Class</title>
<link type='text/css' rel='stylesheet' href='style.css'/>
</head>
<body>
<p>
<?php
class person {
public $isAlive = true;
public $firstname;
public $lastname;
public $age;
public function __construct($firstname, $lastname, $age){
$this->$firstname = $firstname;
$this->$lastname = $lastname;
$this->$age = $age;
}
}
$teacher = new Person("boring", "12345", 12345);
$student = new Person("dan", "Kelly", 47);
echo $student->age;
//echo $teacher->isAlive;
?>
</p>
</body>
</html>
Level 13
You should read through the php documentation for variables http://php.net/manual/en/language.variables.variable.php
$this->$firstname = $firstname; is basically saying "evaluate the value of $firstname as the name of a property, and assign the value of $firstname to it. If the value of $firstname is "Steve", this is the same as $this->Steve = 'Steve'
$this->firstname = $firstname is how you assign a value to the "firstname" property.
Level 5
I see now. Thanks so much for the help 36864. You're awesome!
Level 20
@dk4210 Tip: there's a great series on OOP basics here at Laracasts: https://laracasts.com/series/object-oriented-bootcamp-in-php
Please or to participate in this conversation.