Use static variable in static function

Question

How do I reference a static variable from within a static function in the same class?

I am trying:

class SQL {

public static $partsNetTotalPounds = '...';

public static function margin()
  {
    return '('.$this->partsNetTotalPounds...
  }
}

Ofcourse this does not work because I haven't instantiated the object SQL.

How can this be done?

Answer 1

public static function margin()
  {
    return "(" . self::$partsNetTotalPounds ;
  }

Answer 2

you need to use self keyword

self::$partsNetTotalPounds

Answer 3

Like the other people have pointed out use the self keyword: self::$partsNetTotalPounds.

If the value of the $partsNetTotalPounds is all you need you don't need to access it through the margin method, by the way. Instead you can access it via SQL::$partsNetTotalPounds.

$this is used to access properties of an instance so it does not apply in this case.