I am new to php so please excuse my lack of knowledge. I am using eclipse and have a project with 3 files inside the project. I am creating a find discount class which takes the class object to call a function from another class. The error:
Notice: Undefined variable: GetInfoClass line ..
Fatal error: Call to a member function getAge() on a non-object line ...
I tried to read about it but I cant seem to understand it. Please help. Thanks
formResponse:
include "GetInfo.php";
include "IfDiscount.php";
$IfDiscount= new IfDiscount();
echo $IfDiscount->findDiscount();
class IfDiscount:
class IfDiscount
{
public function findDiscount(){
$Age = $GetInfoClass->getAge();
echo $Age;}}
$GetInfoClass is not available to findDiscount() because it is out of scope. You should pass it to findDiscount() as a parameter to make it available to that method:
public function findDiscount($GetInfoClass){
$Age = $GetInfoClass->getAge();
return $Age;
}
echo $IfDiscount->findDiscount($GetInfoClass);
(You also want to return $Age, not echo it. You already explicitly echo it when you call that method.)
Related
This question already has answers here:
Reference - What does this error mean in PHP?
(38 answers)
Closed 8 years ago.
So I'm refactoring my code to implement more OOP. I set up a class to hold page attributes.
class PageAtrributes
{
private $db_connection;
private $page_title;
public function __construct($db_connection)
{
$this->db_connection = $db_connection;
$this->page_title = '';
}
public function get_page_title()
{
return $this->page_title;
}
public function set_page_title($page_title)
{
$this->page_title = $page_title;
}
}
Later on I call the set_page_title() function like so
function page_properties($objPortal) {
$objPage->set_page_title($myrow['title']);
}
When I do I receive the error message:
Call to a member function set_page_title() on a non-object
So what am I missing?
It means that $objPage is not an instance of an object. Can we see the code you used to initialize the variable?
As you expect a specific object type, you can also make use of PHPs type-hinting featureDocs to get the error when your logic is violated:
function page_properties(PageAtrributes $objPortal) {
...
$objPage->set_page_title($myrow['title']);
}
This function will only accept PageAtrributes for the first parameter.
There's an easy way to produce this error:
$joe = null;
$joe->anything();
Will render the error:
Fatal error: Call to a member function anything() on a non-object in /Applications/XAMPP/xamppfiles/htdocs/casMail/dao/server.php on line 23
It would be a lot better if PHP would just say,
Fatal error: Call from Joe is not defined because (a) joe is null or (b) joe does not define anything() in on line <##>.
Usually you have build your class so that $joe is not defined in the constructor or
Either $objPage is not an instance variable OR your are overwriting $objPage with something that is not an instance of class PageAttributes.
It could also mean that when you initialized your object, you may have re-used the object name in another part of your code. Therefore changing it's aspect from an object to a standard variable.
IE
$game = new game;
$game->doGameStuff($gameReturn);
foreach($gameArray as $game)
{
$game['STUFF']; // No longer an object and is now a standard variable pointer for $game.
}
$game->doGameStuff($gameReturn); // Wont work because $game is declared as a standard variable. You need to be careful when using common variable names and were they are declared in your code.
function page_properties($objPortal) {
$objPage->set_page_title($myrow['title']);
}
looks like different names of variables $objPortal vs $objPage
I recommend the accepted answer above. If you are in a pinch, however, you could declare the object as a global within the page_properties function.
$objPage = new PageAtrributes;
function page_properties() {
global $objPage;
$objPage->set_page_title($myrow['title']);
}
I realized that I wasn't passing $objPage into page_properties(). It works fine now.
you can use 'use' in function like bellow example
function page_properties($objPortal) use($objPage){
$objPage->set_page_title($myrow['title']);
}
I am currently using phpunit for some unit testing. Due to the presence of some protected methods, I had to use a Reflection Class to change the visibility of these methods to public.
The initial methods were called successfully but somehow it gets stuck at a specific method:
Fatal error: Call to undefined method ReflectionClass::create_schema()in
/vagrant/fuelphp/fuel/app/tests/model/repository/jobpost.php on line 54
However, dumping the method via get_method() with var_dump proves that it exists in the class instance:
class ReflectionMethod#2317 (2) {
public $name =>
string(13) 'create_schema'
public $class =>
string(34) 'Model_Repository_Feed'
}
Then the real confusing bit, I decided to use hasMethod() to see if the method exists:
52 echo "If this says 1, class exists: ".$this->_target->hasMethod('create_schema');
53 try {
54 $this->_target->create_schema();
55 }
The result when running says, "yes it exists.... but it doesn't":
If this says 1, class exists: 1
Fatal error: Call to undefined method ReflectionClass::create_schema() in /vagrant/fuelphp/fuel/app/tests/model/repository/jobpost.php on line 54
To clarify this method is public and is inherited from an abstract parent class:
public function create_schema() {
$this->create_schema_exec(self::$_real_schema_name);
}
How can this issue be solved?
you need to get the object of the class that holds the method not the reflection object.
$reflection = new ReflectionClass($className);
$object = $reflection->newInstanceWithoutConstructor();
$object->methodName();
I have the class name Car stored as a static variable in constants. I would like to use this constant to call the function a. One options is to use an intermediate variable $tmp. I could then call $tmp::a(). Is there a way to do this in one statement? My attempt is below.
class Car{
public static function a(){
return 'hi';
}
}
class Constants{
public static $use='Car';
}
$tmp=Constants::$use;
echo(${Constants::$use}::a());
IDEOne link
Output is as follows
PHP Notice: Undefined variable: Car in /home/mU9w5e/prog.php on line 15
PHP Fatal error: Class name must be a valid object or a string in /home/mU9w5e/prog.php on line 15
There is always call_user_func():
echo call_user_func( array( Constants::$use, 'a'));
IDEOne Demo
The only alternative that I could find to #nickb's way was using something I've never heard of, but hey that's what SO is for!
I found the ReflectionMethod, which seems to be more bloated than the call_user_func, but was the only alternative way that I could find:
<?php
class Car{
public static function a(){
return 'hi';
}
}
class Constants{
public static $use='Car';
}
$reflectionMethod = new ReflectionMethod(Constants::$use, 'a');
echo $reflectionMethod->invoke(new Car());
The above is a bit of a failed experiment as Casebash doesn't want to create temp variables.
As CORRUPT mentioned in the comments, it is possible to use the following although was tested on PHP version 5.4.14 (which I am unable to do):
echo (new ReflectionMethod(Constants::$use, 'a'))->invoke(new Car());
I have crazy solution, but you should never use it :^ )
echo ${${Constants::$use} = Constants::$use}::a();
the class below is part of an mvc structure im building for my website. the class is there to produce a page if index.php is called without any request in the url. if that is good practice or not I do not know. Im new to php, and this is the first time i implement an mvc structure.
<?php
class Default_Model
{
private $defaultPage = array
(
'headline' => 'JOBBSÖKAREN',
'instruction' => 'logga in nedanför'
);
public function __construct()
{
}
public function getContent()
{
line 17 return $defaultPage;
}
}
?>
here is the error message:
Notice: Undefined variable: defaultPage in /home/mengus/dev/www/models/default.php on line 17
so what I dont get is why the array is undefined. I use similar code in other classes and it works just fine. is it a scope issue? I seem to have gone error blind from staring at this :)
thanks for help.
To access the fields you need to use $this and -> operator
return $this->defaultPage;
I have a problem in calling a function that the name is being stored in an array.
class tempClass {
function someFunction() {
$tempArray = array('functionName' => 'tempFunction');
$tempArray['functionName']();
}
function tempFunction() {
echo "inside function";
}
}
It gives me an error:
"Fatal error: Call to undefined function tempFunction() in /..... line..".
Line number is the line where the function is being called, $tempArray['functionName']();
But if called the method_exists(), it shows that the method is exists. It is very confusing. Can anyone please help me out? Thanks.
Use call_user_func() , like this:
call_user_func($tempArray['functionName']);
UPDATE:
As you want to call a method of a class from inside that class, use the following instead:
call_user_func(array($this, $tempArray['functionName']));
See working demo
Well you ask if the method exists inside the class or object, but you call it without that scope. That won't work...
Try this instead:
call_user_method($tempArray['functionName'],$this);
Just saw that call_user_method() is depreciated. Use call_user_func() as answered by Nelson instead.