类的学习

类的例子

class Student(object):
    def __init__(self, name,number,grade,level):
        self.name = name
        self.number = number
        self.grade = grade
        self.level = level
        self.times = len(level.split(' '))
    def p(self):
        return "{}'s student number is {}, and his grade is {}. He submitted {} assignments, each with a grade of {}".format(self.name,self.number,self.grade,self.times,self.level)
name = input()
number = input()
grade = int(input())
level = input()
student = Student(name,number,grade,level)
print(student.p())

class Person:
  def __init__(mysillyobject, name, age):
    mysillyobject.name = name
    mysillyobject.age = age

  def myfunc(abc):
    print("Hello my name is " + abc.name)

p1 = Person("Bill", 63)
p1.myfunc()

应用时直接添加类的属性

class Employee:
    def __init__(self,name,salary):
        self.name = name
        self.salary =salary
    def printclass(self):
        try:
            print("{}'salary is {}, and his age is {}".format(self.name,self.salary,self.age))
        except:
            print("Error! No age")
       
name = input()
salary =int(input())
age = int(input())
e =Employee(name,salary)
e.printclass()#没有找到age
e.age = age #添加类的属性
e.printclass()

hasattr(obj,name)

• obj 指的是某个类的实例对象
• name 表示指定的属性名或方法名
• return    True 或者 False

class Employee:
    def __init__(self, name, salary):
        self.name = name
        self.salary = salary

    def printclass(self):
        try:
            print(
                "{}'salary is {}, and his age is {}".format(
                    self.name, self.salary, self.age
                )
            )
        except:
            print("Error! No age")
name = input()
salary =int(input())
age = int(input())
e = Employee(name,salary)
print(hasattr(e,"age")) #hassttr用法
e.age =age
e.printclass()

pass 语句

类定义不能为空，但是如果您处于某种原因写了无内容的类定义语句，请使用 pass 语句来避免错误。

实例

class Person:
  pass