开始学习Python面向对象编程

class Person:
　　pass #pass语句表示一个空类

p = Person()
print(p)

$ python simplestclass.py
<__main__.Person object at 0x019F85F0>
#我们已经在 __main__ 模块中有了一个 Person 类的实例 

class Person:
    def sayHi(self):
    #定义函数的时候有self
    print(‘Hello, how are you?‘)

p = Person()
p.sayHi()
# This short example can also be written as Person().sayHi()

class Person:
    def __init__(self, name):
        self.name = name
    def sayHi(self):
    　　print(‘Hello, my name is‘, self.name)
    
p = Person(‘Swaroop‘)    

#Filename:claaOrInsVar
class animal:
    population = 0

    def __init__(self,name):
        self.name = name
        animal.population += 1

    def sayHi(self):
        print("My name is " + self.name)

    def howMany ( ): #这个函数没有传递参数self
  #      print(‘We have ‘ + animal.population + ‘animals‘)
  #使用上面的代码后程序报错“    print(‘We have ‘ + animal.population + ‘animals‘)
  #TypeError: must be str, not int”
  #animal.population 无法自动和字符串进行连接，java中是可以有表达式的自动提升的，python中却不能这样做
        print(‘We have {0} animals.‘.format(animal.population))
an1 = animal(‘dogWW‘)
an1.sayHi()
an2 = animal(‘catMM‘)
an2.sayHi()
animal.howMany()

class SchoolMenber:
    def __init__(self,name,age):
        self.name = name
        self.age = age
    def tell(self):
        print(‘name:{0} age:{1}‘.format(self.name,self.age))

class Teacher(SchoolMenber):
    def __init__(self,name,age,salary):
        SchoolMenber.__init__(self,name,age)#这里的self不要忘了写啊
        self.salary = salary

    def tell(self):
        SchoolMenber.tell(self)
        print(‘salary: {0}‘.format(self.salary))

class Student(SchoolMenber):
    def __init__(self,name,age,mark):
        SchoolMenber.__init__(self,name,age)
        self.mark = mark

    def tell(self):
        SchoolMenber.tell(self)
        print(‘mark:{0}‘.format(self.mark))

stu = Student(‘Jenny‘,20,95)
tec = Teacher(‘Mary‘,50,5000)
menbers = [stu,tec]
for menber in menbers:
    menber.tell()