March 3, 2013
How can I get the child properties without the parent properties?
Question by user1020317
I’ve something like the following:
class a {
private $firstVar;
function foo(){
print_r( get_class_vars( 'b' ) );
}
}
class b extends a{
public $secondVar;
}
a::foo();
print_r( get_class_vars( 'b' ) );
The output is
Array ( [secondVar] => [firstVar] => )
Array ( [secondVar] => )
I pressume this is because when get_class_vars(‘b’) is called within a it has access to firstVar, but how can I get the function foo() to output just the class ‘b’ variables, without the parent variables?
Theres a solution on http://php.net/manual/en/function.get-class-vars.php which involves getting the a variables, then getting all a and b variables and then removing the ones that are in both, leaving just the b variables. But this method seems tedious. Is there another way?
Workaround I’m currently using:
class a {
private $firstVar;
function foo(){
$childVariables = array();
$parentVariables = array_keys( get_class_vars( 'a' ));
//array of 'a' and 'b' vars
$allVariables = array_keys( get_class_vars( get_class( $this ) ) );
//compare the two
foreach( $allVariables as $index => $variable ){
if( !(in_array($variable, $parentVariables))){
//Adding as keys so as to match syntax of get_class_vars()
$childVariables[$variable] = "";
}
}
print_r( $childVariables );
}
}
class b extends a{
public $secondVar;
}
$b = new b;
$b->foo();
Answer by Starx
You must be running on lower PHP version. It works fine on codepad on your same code.
Demo: http://codepad.org/C1NjCvfa
However, I will provide you with an alternative. Use Reflection Clases:
public function foo()
{
$refclass = new ReflectionClass(new b());
foreach ($refclass->getProperties() as $property)
{
echo $property->name;
//Access the property of B like this
}
}
