Get two values returned from class - php

Question

I am trying to understand object oriented PHP programming and wrote a small class to learn. I am having trouble understanding why its not working the way I intend. I have two variables inside the class method hello() $result and $test. I am trying to access the data that is stored in those two variables and print it to the screen. I know I can just call an echo inside the method but I am trying to get it to echo outside of it.
What I get printed to the screen is 88 it does not print out the second variable $test. I am trying to understand why thats happening. My lack of understanding probably shows in the code.
<?php
class simpleClass{
public function hello($result,$test) {
$result = 4+4;
$test = 10+5;
return $result;
return $test;
}
}
$a = new simpleClass;
echo $a->hello();
echo $a->hello($result, $test);
?>

Answer 1

you can return a list or array
public function hello($result,$test) {
$result = 4+4;
$test = 10+5;
return array($result, $test);
}

Answer 2

Use parameter referencing :
class simpleClass{
public function hello(&$result, &$test) {
$result = 4+4;
$test = 10+5;
}
}
$a = new simpleClass;
$result=''; $test='';
$a->hello($result, $test);
echo $result;
echo '<br>';
echo $test;
8
15
To clarify, when you add & to a function param, the value of that param - if you change or manipulate it inside the function - is handled back to your original variable passed. So you dont even have to return a result, and lets say pack it into an array or stdObject and unpack it afterwards. But you can still return something from the function, eg
$ok = $a->hello($result, $test);
as a flag to indicate if the calculation went right, for instance.

Answer 3

You cannot have multiple return statements in the same function because of the way return works. When a return statement is encountered the function stops executing there and then, passing back to the caller. The rest of the function never runs.

Answer 4

The complicated answer is to use a model.
class simpleResultTestModel {
public $result;
public $test;
public function __construct($result,$test) {
$this->result = $result;
$this->test = $test;
}
}
class simpleClass {
public function hello($result=4, $test=10) {
$result = $result+4;
$test = $test+5;
return new simpleResultTestModel($result, $test);
}
}
This way, you know simpleClass->hello() will always return an instance of simpleResultTestModel.
Also, I updated your hello method definition. You have two parameters, but don't actually apply them; I took the liberty of setting default values and then used them in the computation.
Usage:
$a = new simpleClass();
$first = $a->hello();
echo $first->result;
echo $first->test;
$second = $a->hello($first->result,$first->test);
echo $second->result;
echo $second->test;
I would try to stay away from passing by reference (especially within a class definition) unless you have a legitimate reason for doing so. It is bad practice when creating instances of classes (i.e. "sticky values" if you will).