This obj is the instance that has the descriptor.
obj是具有描述符的实例。
And the way area can be calculated for rect obj is.
然后我们就可以这样调用计算它的面积了。
It is recommended not to use OBJ (although it is still supported).
不建议使用对象(虽然它仍然支持)。
It is recommended not to use OBJ (although it is still supported).
不建议使用对象(虽然它仍然支持)。
应用推荐