note 88665 deleted from language.oop5.basic by cmb
| From: | cmb@php.net | Date: | Mon, 21 Nov 2016 18:13:22 +0000 |
| Subject: | note 88665 deleted from language.oop5.basic by cmb | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-207267@lists.php.net to get a copy of this message | ||
Note Submitter: ialsoagree
----
I think it's worth mentioning that if you define a function inside of an object method, that
function cannot refer to "$this" - doing so will result in PHP reporting a fatal error:
Fatal error: Using $this when not in object context
<?php
class MyClass {
public $message = 'Hello';
public function MyClassFunction() {
function InnerFunction() {
echo $this->message; // Reports a fatal error
}
innerFunction();
}
}
$class = new MyClass;
$class->MyClassFunction();
?>
This issue cannot be solved by using the Scope Resolution Operator if you're trying to access a
variable:
<?php
class MyClass {
public $message = 'Hello';
public function MyClassFunction() {
function InnerFunction() {
echo MyClass::message; // Reports a fatal error
}
innerFunction();
}
}
$class = new MyClass;
$class->MyClassFunction();
?>
Additionally, you can NOT create a public function to access that variable:
<?php
class MyClass {
public $message = 'Hello';
public function MyClassFunction() {
function InnerFunction() {
MyClass::echoSomething();
}
innerFunction();
}
public function echoSomething() {
echo $this->message; // Reports a fatal error
}
}
$class = new MyClass;
$class->MyClassFunction();
?>
Note that in this last case, the error is generated on the line below echoSomething function
declaration, not at MyClass::echoSomething();
However, it is worth noting that when called directly, echoSomething works fine:
<?php
class MyClass {
public $message = 'Hello';
public function MyClassFunction() {
function InnerFunction() {
MyClass::echoSomething();
}
innerFunction();
}
public function echoSomething() {
echo $this->message; // Echoes 'Hello'
}
}
$class = new MyClass;
$class->echoSomething();
?>