php get_called_class()函数与get_class()函数的区别

class Foo{
      public function test(){
         var_dump(get_class());
      }

      public function test2(){
        var_dump(get_called_class());
      }

      public static function test3(){
        var_dump(get_class());
      }

      public static function test4(){
        var_dump(get_called_class());
      }
   }

   class B extends Foo{

   }

   $B=new B();
   $B->test();
   $B->test2();
   Foo::test3();
   Foo::test4();
   B::test3();
   B::test4();

输出结果：
string 'Foo' (length=3)
string 'B' (length=1)
string 'Foo' (length=3)
string 'Foo' (length=3)
string 'Foo' (length=3)
string 'B' (length=1)