Object Oriented Programming -> Operator [duplicate] - php

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Reference - What does this symbol mean in PHP?
So I've been reading through the book PHP Solutions, Dynamic Web Design Made Easy by David Powers. I read through the short section on Object Oriented PHP, and I am having a hard time grasping the idea of the -> operator. Can anyone try to give me a solid explanation on the -> operator in OOP PHP?
Example:
$westcost = new DateTimeZone('America/Los_Angeles');
$now->setTimezone($westcoast);
Also,a more general example:
$someObject->propertyName

Answer 1

The -> operator in PHP refers to either a function or a variable inside a class.
<?php
class Example {
public $variableInClass = "stringContent";
public function functionInClass() {
return "functionReturn";
}
}
$example = new Example();
var_dump($example->variableInClass); //stringContent
var_dump($example->functionInClass()); //functionReturn
?>
Do note that if we're talking about static classes (different purpose), you use :: instead:
<?php
class Example {
public static $variableInClass = "stringContent";
public static function functionInClass() {
return "functionReturn";
}
}
var_dump($example::$variableInClass); //stringContent
var_dump($example::functionInClass()); //functionReturn
?>

Answer 2

$someObject->propertyName can be read as:
return value stored in propertyName from object $someObject
$someObject->methodName() can be read as:
execute methodName from object $someObject

Answer 3

Classes and objects 101:
A class is defined as such:
class MyClass {
public $value1;
public function getValue() {
return $this->value;
}
}
We now defined a class with a single property, and a single function. To use these, we need to create an 'instance' of this object:
$myObject = new MyClass();
To use the property or function, we use the -> operator:
echo $myObject->value1;
echo $myObject->getValue();
Put a little bit more abstractly.. the function getValue is defined in this object. By using the -> operator on an instance of our class, what PHP does is effectively just call the function, just like any other function.. but before it gets called $this is assigned to the current object.
Hope this helps, if not.. I would simply recommend reading about OOP basics.