请问PHP7.2 ZEND内核中如何获取类定义的常量？

Created 6 years ago by Scarecrow, Updated 6 years ago Revision #1 1785 views 0 likes 0 collects

p=zend_get_constant_ex(zend_string_init("test", 4, 1), Z_OBJCE_P(getThis()), getThis()->u2.access_flags);

这样去拿取类常量p始终是空值？求大佬告知方法