#!/usr/bin/env python3
# -*- coding: utf-8 -*-
class Screen():

    @property
    def Width(self):
        return self._width

    @Width.setter
    def Width(self,value):
        if not isinstance(value, int):
            raise ValueError('score must be an integer!')
        if value <= 0:
            raise ValueError('score must >0')
        self._width=value

    @property
    def Heigth(self):
        return self._heigth

    @Heigth.setter
    def Heigth(self,value):
        if not isinstance(value, int):
            raise ValueError('score must be an integer!')
        if value <= 0:
            raise ValueError('score must >0')
        self._heigth=value

    @property
    def Resolution(self):
        return str('%d * %d'%(self._width,self._heigth))


s=Student()
s.Width =1024#这里的Width不是属性名，是方法名，属性名是_width，可用dir(s)查看
s.Heigth =768#这里的Hidth不是属性名，是方法名，属性名是_hidth，可用dir(s)查看
s.Resolution #这里的Resolution不是属性名，是方法名，