From the string name of a class, can I get a static variable?

Given the string name of a class in PHP, how can I access one of its static variables?

What I'd like to do is this:

$className = 'SomeClass'; // assume string was actually handed in as a parameter
$foo = $className::$someStaticVar;

...but PHP gives me a lovely "Parse error: syntax error, unexpected T_PAAMAYIM_NEKUDOTAYIM", which apparently is a Hebrew name for the d开发者_Python百科ouble colon(::).

Update: Unfortunately, I have to use PHP 5.2.X for this.

Update 2: As MrXexxed guessed, the static variable is inherited from a parent class.

Reflection will do it

A coworker just showed me how to do this with reflection, which works with PHP 5 (we're on 5.2), so I thought I'd explain.

$className = 'SomeClass';

$SomeStaticProperty = new ReflectionProperty($className, 'propertyName'); 
echo $SomeStaticProperty->getValue();

See http://www.php.net/manual/en/class.reflectionproperty.php

A similar trick works for methods.

$Fetch_by_id = new ReflectionMethod($someDbmodel,'fetch_by_id');
$DBObject = $Fetch_by_id->invoke(NULL,$id);
// Now you can work with the returned object
echo $DBObject->Property1;
$DBObject->Property2 = 'foo';
$DBObject->save();

See http://php.net/manual/en/class.reflectionmethod.php and http://www.php.net/manual/en/reflectionmethod.invoke.php

Which version of PHP are you running? I believe above 5.3.x this is allowed but before that it isn't.

EDIT: here you go as of PHP 5.3.0 it's allowed Example #2

echo $classname::doubleColon(); // As of PHP 5.3.0

Edit: For variables use

echo $classname::$variable; // PHP 5.3.0 +

here's the link

Edit 3: Try this link the answer from there seems like it would apply to your situation.

That's only possible in PHP 5.3 and later with late static bindings.

The workaround for older versions of PHP that first comes to my mind is — please don't hurt me — using eval():

if (class_exists($className))
{
    eval('$foo = ' . $className . '::$someStaticVar;');
}

By the way, when accessing static variables, the $ before the variable name is needed, as in $someStaticVar.

You might have to use the reflection classes. http://www.php.net/manual/en/reflectionfunctionabstract.getstaticvariables.php

Or use a simple string eval: print "{$className::$someStaticVar}", which replaces $className before looking up the ::$someStaticVar. Not sure about PHP < 5.2 though.