day24

1.面向物件

# 1、如何基於面向物件的思想寫程式
# 例1
# 學生的資料
# stu_name = "egon"
# stu_age = 18
# stu_gender = "male"
​
# 學生的功能
# def choose(name, age, gender):
#   print('%s:%s:%s 正在選課' % (name, age, gender))
​
# choose(stu_name,stu_age,stu_gender)
​
# 例2：基於物件式的思想進行改寫
# def choose(stu_self):
#   print('%s:%s:%s 正在選課' % (stu_self["stu_name"], stu_self["stu_age"],stu_self["stu_gender"],))
 
#
# stu_obj = {
#   "stu_name": "egon",
#   "stu_age": 18,
#   "stu_gender": "male",
#   "choose":choose
# }
​
# print(stu_obj["stu_name"])
# stu_obj["choose"](stu_obj)
​
# python提供專門的語法來更漂亮地實現面向物件程式設計，什麼語法？？？
​
'''
學生物件1
   資料：
​
     名字 = "馮瘋子"
     年齡 = 18
     性別 = "female"
​
​
學生物件2
   資料：
​
     名字 = "郭靖"
     年齡 = 19
     性別 = "male"
 
​
​
學生物件3
   資料：
     名字 = "大雕"
     年齡 = 200
     性別 = "male"
​
​
學生的類
   相同的資料
     學校 = "oldboy"
   相同的功能
     選課
​
​
'''
# 類體程式碼會在類定義階段立刻執行，然後將產生的名字都丟到類的名稱空間中
class Student:
  # 相同的資料
  school = "oldboy"
​
  # 相同的功能
  def choose(self):
    print("正在選課")
​
​
  # print('====>')
​
stu_obj1=Student()
stu_obj2=Student()
stu_obj3=Student()
 
​
stu_obj1.name = "馮瘋子" # stu1_obj1.__dict__["name"] = "馮瘋子"
stu_obj1.age = 18
stu_obj1.gender = "female"
​
stu_obj2.name = "郭靖"
stu_obj2.age = 19
stu_obj2.gender = "male"
​
stu_obj3.name = "大雕"
stu_obj3.age = 200
stu_obj3.gender = "male"
​
# print(stu_obj1.name)
# stu_obj1.school = "xxx"
# print(stu_obj1.school)
​
# print(Student.__dict__)
print(stu_obj1.__dict__)
print(stu_obj2.__dict__)
print(stu_obj3.__dict__)

2.初始化方法

# =============================>例1
# class Student:
#   school = "oldboy"
#
#   def choose(self):
#     print("正在選課")
#
# stu_obj1=Student()
# stu_obj2=Student()
# stu_obj3=Student()
​
# stu_obj1.name = "馮瘋子"
# stu_obj1.age = 18
# stu_obj1.gender = "female"
#
# stu_obj2.name = "郭靖"
# stu_obj2.age = 19
# stu_obj2.gender = "male"
#
# stu_obj3.name = "大雕"
# stu_obj3.age = 200
# stu_obj3.gender = "male"
​
# # ============================>例2：
# class Student:
#   school = "oldboy"
#
#   def choose(self):
#     print("正在選課")
#
# stu_obj1 = Student()
# stu_obj2 = Student()
# stu_obj3 = Student()
#
# def init(obj, x, y, z):
#   obj.name = x
#   obj.age = y
#   obj.gender = z
#
# init(stu_obj1, "馮瘋子", 18, "female")
# init(stu_obj2, "郭靖", 19, "male")
# init(stu_obj3, "大雕", 200, "male")
​
# ============================>例3：
class Student:
  school = "oldboy"
​
  #       空物件
  def __init__(obj, x, y, z):
    obj.name = x
    obj.age = y
    obj.gender = z
    # return None # 只能返回None
​
  def choose(self):
    print("正在選課")
​
# 呼叫類：
# 1、建立一個空物件與類相關
# 2、把空物件、"馮瘋子", 18, "female"一起傳給__init__方法，完成物件的初始化
# 3、賦值符號把初始化好的物件的記憶體地址繫結變數名stu_obj1
stu_obj1 = Student("馮瘋子", 18, "female")
stu_obj2 = Student("郭靖", 19, "male")
stu_obj3 = Student("大雕", 200, "male")
​
​
print(Student.__dict__)
print(stu_obj1.__dict__)

3.屬性查詢

# 優先順序
# 先從物件的字典裡找，沒有，再去類的字典中找
class Student:
  school = "oldboy"
​
  def __init__(obj, x, y, z):
    obj.name = x
    obj.age = y
    obj.gender = z
​
  def choose(self):
    print("%s 正在選課" %self.name)
​
stu_obj1 = Student("馮瘋子", 18, "female")
stu_obj2 = Student("郭靖", 19, "male")
stu_obj3 = Student("大雕", 200, "male")
​
# 1、類中定義的資料是直接共享給所有物件使用的
# print(id(stu_obj1.school))
# print(id(stu_obj2.school))
# print(id(stu_obj3.school))
# print(id(Student.school))
​
# Student.school="xxx"
# print(stu_obj1.school)
# print(stu_obj2.school)
# print(stu_obj3.school)
​
# print(Student.choose)
# print(stu_obj1.choose)
# print(stu_obj2.choose)
# print(stu_obj3.choose)
​
# 2、類中定義的函式是繫結給所有物件用的，繫結給誰就應該由哪個物件來呼叫
# 物件.繫結方法()會把物件當作第一個引數傳入
#  類.函式()就是一個函式的玩法，沒有自動傳參的效果
​
# Student.choose(123123123)
stu_obj3.choose()
stu_obj2.choose()
stu_obj1.choose()