Python new class

Class (CLASS): Defines the behavior that a large class of objects have.
When we create objects based on this class, each object has this common behavior.
实例化: Create an object from a class

1. Create a class

Use the keyword class to create a
class The first letter of the class name is capitalized, with or without parentheses
The class we define should contain two parts: attributes + functions

Let's build a simple class计算器的类Calculator

class Calculator:
    # 固有属性项
    name = 'Good Calculator' 
    price = 44
    
    # 初始化类的属性
    def __init__(self,name,price,H,width=10,weight=5):
        self.n = name
        self.p = price
        self.h = H
        self.wi = width
        self.we = weight
    # 定义内部函数，实现相应功能
    def add(self,x,y):
        print(self.name)  # 使用self调用属性name
        result=x+y
        print(result)
        
    def minus(self,x,y):
        result=x-y
        print(result)
    
    def time(self,x,y):
        result=x*y
        print(result)
    
    def divide(self,x,y):
        result=x/y
        print(result)

2. Use class

Instantiating classes in python does not need to use the keyword new
The instantiation of classes is similar to [function calls]

# 定义实例使用该类
x = Calculator('FF',20,30)
# 'FF'代表 name
# 20 代表 price
# 30 代表 H
# 打印实例的属性进行查看 【实例名字.属性】

Here are the assigned attributes in the instance

print('默认名称:',x.name)
print('默认的价格属性:',x.price)
# 注意，这里x.name和x.n不一样【x.name是初始；x.n传入了变量】
print('实例中赋予的价格属性:',x.p)
print('实例中高度值:',x.h)
print('实例中的宽度:',x.wi)
print('实例中的重量:',x.we)
print('实例中名称:',x.n)

call a method in the class

add_ = x.add(3,4)
minus_ = x.minus(3,4)
times_ = x.time(3,4)
divide_ = x.divide(3,4)

learning link

• How to create and use classes in Python