Calling User Defined Function In User Defined Class

Question

I am trying to create a custom class that will handle mailing for me.

Here is my class (mailerclass.php) :

class Mailer {

        // Private fields
        private $to;
        private $subject;
        private $message;

        // Constructor function
        function __construct($to, $subject, $message) {
            $to = $to;
            $subject = $subject;
            $message = $message;
        }   

        // Function to send mail with constructed data.
        public function SendMail() {

            if (mail($to, $subject, $messagecontent)) {
                return "Success";
            }
            else {
                return "Failed";    
            }           
        }

    }

When I try to call it here (index.php) I get a "Call to undefined function SendMail()" message?

if ($_SERVER['REQUEST_METHOD'] == "POST") {

        // Import class
        include('mailerclass.php');

        // Trim and store data
        $name = trim($_POST['name']);
        $email = trim($_POST['email']);
        $message = trim($_POST['message']);


        // Store mail data
        if ($validated == true) {

            // Create new instance of mailer class with user data
            $mailer = new Mailer($to, $subject, $message);          

            // Send Mail and store result
            $result = $mailer.SendMail();
        }

Why does this happen ??

Answer 1

Dot . is use for concatenate . You use -> to access member of class

$result = $mailer->SendMail();

Answer 2

You don't call class methods with a dot. You call class methods (not static) with -> like:

$result = $mailer->SendMail();

Besides you need to set your properties with $this-> (again if not static) change the content of your contstructor to:

$this->to = $to;
$this->subject = $subject;
$this->message = $message;

Same goes for your mail() function:

mail($this->to, $this->subject, $this->messagecontent)

You saw me mentioning static a few times, if you ever want to access a static property or method in your class you can use self::

Answer 3

. is a contact operator, to access member of a class both variable and functions use -> operator use the below code:
$result = $mailer->SendMail();