组合应用:
class Teacher: def __init__(self,name,age,sex,salary,level): self.name=name self.age=age self.sex=sex self.salary=salary self.level=level def walk(self): print('%s is walking'%self.name) def teach(self): print('%s is teaching'%self.name) def tell_info(self): print(''' ----------%s info-------- NAME:%s AGE:%s SEX:%s SAL:%s LEVEL:%s '''%(self.name,self.name,self.age,self.sex,self.salary,self.level))class Date: def __init__(self,year,mon,day): self.year=year self.mon=mon self.day=day def tell_birth(self): print('%s-%s-%s'%(self.year,self.mon,self.day))
alex=Teacher('alex',84,'male',30000,-1) Birth=Date(1900,13,43) alex.birth=Birth alex.tell_info() print(alex.birth) #<__main__.Date object at 0x00000000027B2860> alex.birth.tell_birth() 运行结果: ----------alex info-------- NAME:alex AGE:84 SEX:male SAL:30000 LEVEL:-1 <__main__.Date object at 0x00000000027B2860> 1900-13-43
改动Date类,表明是谁的生日:
class Date: def __init__(self,name,year,mon,day): self.name=name self.year=year self.mon=mon self.day=day def tell_birth(self): print('%s:%s-%s-%s'%(self.name,self.year,self.mon,self.day))alex=Teacher('alex',84,'male',30000,-1)Birth=Date(alex.name,1900,13,43)alex.birth=Birthalex.birth.tell_birth()运行结果:alex:1900-13-43
组合的应用:
class Teacher: def __init__(self,name,age,sex,salary,level): self.name=name self.age=age self.sex=sex self.salary=salary self.level=level def walk(self): print('%s is walking'%self.name) def teach(self): print('%s is teaching'%self.name) def tell_info(self): print(''' ----------%s info-------- NAME:%s AGE:%s SEX:%s SAL:%s LEVEL:%s '''%(self.name,self.name,self.age,self.sex,self.salary,self.level))class Student: def __init__(self,name,age,sex,group): self.name=name self.age=age self.sex=sex self.group=group def walk(self): print('%s is walking'%self.name) def study(self): print('%s is studying'%self.name) def tell_info(self): print(""" -------%s info------- NAME:%s AGE:%s SEX:%s GROUP:%s """%(self.name,self.name,self.age,self.sex,self.group))class Course: def __init__(self,name,price,period): self.name=name self.price=price self.period=period def tell_course(self): print(''' ------%s info------ course name:%s course price:%s course period:%s '''%(self.name,self.name,self.price,self.period))alex=Teacher('alex',84,'male',30000,-1)xiaohuang=Student('xiaohuang',73,'male','group8')python=Course('Python',15800,'6 mons')linux=Course('Linux',12800,'3 mons')go=Course('Go',9800,'4 mons')alex.courses=[]alex.courses.append(python)alex.courses.append(go)print(alex.courses) #[<__main__.Course object at 0x0000000001EAA128>, <__main__.Course object at 0x0000000001E98CC0>]xiaohuang.courses=[]xiaohuang.courses.append(python)print(xiaohuang.courses) #[<__main__.Course object at 0x0000000001EAA128>]运行结果:[<__main__.Course object at 0x0000000001EAA128>, <__main__.Course object at 0x0000000001E98CC0>][<__main__.Course object at 0x0000000001EAA128>]
进一步优化,可以查看对象的课程:
class Teacher: def __init__(self,name,age,sex,salary,level): self.name=name self.age=age self.sex=sex self.salary=salary self.level=level self.courses = [] def walk(self): print('%s is walking'%self.name) def teach(self): print('%s is teaching'%self.name) def tell_info(self): print(''' ----------%s info-------- NAME:%s AGE:%s SEX:%s SAL:%s LEVEL:%s '''%(self.name,self.name,self.age,self.sex,self.salary,self.level)) def tell_course(self): #self=egon if 'courses' in self.__dict__: #'courses' in egon.__dict__ for obj in self.courses: obj.tell_course()class Course: def __init__(self,name,price,period): self.name=name self.price=price self.period=period def tell_course(self): print(''' ------%s info------ course name:%s course price:%s course period:%s '''%(self.name,self.name,self.price,self.period))egon=Teacher('egon',18,'male',30000,10)python=Course('Python',15800,'6 mons')linux=Course('Linux',12800,'3 mons')go=Course('Go',9800,'4 mons')egon.courses.append(python)egon.courses.append(go)egon.tell_course()
我们需要注意一点:
序列化:
import picklexiaohuang=Student('xiaohuang',73,'male','group8')python=Course('Python',15800,'6 mons')linux=Course('Linux',12800,'3 mons')go=Course('Go',9800,'4 mons')xiaohuang.courses.append(python)xiaohuang.courses.append(go)res=pickle.dumps(xiaohuang)print(res)with open('studentdb.pkl','wb') as f: f.write(res)运行结果:b'\x80\x03c__main__\nStudent\nq\x00)\x81q\x01}q\x02(X\x04\x00\x00\x00nameq\x03X\t\x00\x00\x00xiaohuangq\x04X\x03\x00\x00\x00ageq\x05KIX\x03\x00\x00\x00sexq\x06X\x04\x00\x00\x00maleq\x07X\x05\x00\x00\x00groupq\x08X\x06\x00\x00\x00group8q\tX\x07\x00\x00\x00coursesq\n]q\x0b(c__main__\nCourse\nq\x0c)\x81q\r}q\x0e(h\x03X\x06\x00\x00\x00Pythonq\x0fX\x05\x00\x00\x00priceq\x10M\xb8=X\x06\x00\x00\x00periodq\x11X\x06\x00\x00\x006 monsq\x12ubh\x0c)\x81q\x13}q\x14(h\x03X\x02\x00\x00\x00Goq\x15h\x10MH&h\x11X\x06\x00\x00\x004 monsq\x16ubeub.'
注意:json不能序列化对象,我们应该用pickle
反序列化:
with open('studentdb.pkl','rb') as f: res=f.read() obj=pickle.loads(res) print(obj) obj.tell_info()运行结果: ------Python info------ course name:Python course price:15800 course period:6 mons ------Go info------ course name:Go course price:9800 course period:4 mons
反序列化一定要基于类在内存里面
实现与用户交互:
class Student: def __init__(self,name,age,sex,group): self.name=name self.age=age self.sex=sex self.group=group self.courses = [] def study(self): print('%s is studying'%self.name) def tell_info(self): print(""" -------%s info------- NAME:%s AGE:%s SEX:%s GROUP:%s """%(self.name,self.name,self.age,self.sex,self.group)) def tell_course(self): if 'courses' in self.__dict__: for obj in self.courses: obj.tell_course()name=input('user: ').strip()age=int(input('age: ').strip())sex=input('sex: ').strip()group=input('group: ').strip()xiaohuang=Student(name,age,sex,group)xiaohuang.tell_info()运行结果:user: xiaohuangage: 73sex: malegroup: group8 -------xiaohuang info------- NAME:xiaohuang AGE:73 SEX:male GROUP:group8
简洁的写法:
class Student: def __init__(self,name,age,sex,group): self.name=name self.age=age self.sex=sex self.group=group self.courses = [] def study(self): print('%s is studying'%self.name) def tell_info(self): print(""" -------%s info------- NAME:%s AGE:%s SEX:%s GROUP:%s """%(self.name,self.name,self.age,self.sex,self.group)) def tell_course(self): if 'courses' in self.__dict__: for obj in self.courses: obj.tell_course()class Course: def __init__(self, name, price, period): self.name = name self.price = price self.period = period def tell_course(self): print(''' ------%s info------ course name:%s course price:%s course period:%s ''' % (self.name, self.name, self.price, self.period))import picklexiaohuang=Student('xiaohuang',18,'male','group8')with open('studentdb.pkl','wb') as f: pickle.dump(xiaohuang,f)with open('studentdb.pkl','rb') as f: obj=pickle.load(f) obj.tell_info()运行结果: -------xiaohuang info------- NAME:xiaohuang AGE:18 SEX:male GROUP:group8
模块的运用:
先定义一下几个文件:
各文件内容如下:
models.py:
class Student: def __init__(self,name,age,sex,group): self.name=name self.age=age self.sex=sex self.group=group self.courses = [] def study(self): print('%s is studying'%self.name) def tell_info(self): print(""" -------%s info------- NAME:%s AGE:%s SEX:%s GROUP:%s """%(self.name,self.name,self.age,self.sex,self.group))
pickle_obj.py:
import pickledef get_obj(): with open('studentdb.pkl', 'rb') as f: res=f.read() obj=pickle.loads(res) obj.tell_info() with open('studentdb.pkl', 'rb') as f: obj = pickle.load(f) obj.tell_info()
start.py:
from models import Studentimport pickle_objpickle_obj.get_obj()
还有我们事先准备好的studentdb.pkl文件。
运行start.py文件,效果如下:
-------xiaohuang info------- NAME:xiaohuang AGE:18 SEX:male GROUP:group8
接下来看开发软件的规范:
bin文件夹一般放可执行文件,conf文件夹一般放可配置文件,db文件夹一般方法数据文件,还有log目录,lib目录(一般存放常用小工具),src目录放核心,类,逻辑等
开发选课系统:
main函数提供菜单,用户可以选择
今天作业:老师,学生,课程三个类实现选课系统