如何将自定义拆分字符串的scalc函数整合至含基础数学方法的calculator类？

我写了一个scalc函数，它能从单个字符串（格式如"N1, N2, operator"）里提取三个参数，拆分后执行计算并返回结果。现在纠结是给它单独创建类，还是整合到现有的接收两个输入的calculator类里？尝试整合的时候遇到了困难，scalc里包含strip格式化处理，相关代码如下：

class calculator:
    def __init__(self,a,b):
        self.Num1 = a
        self.Num2 = b
    def add(self):
        return self.Num1 + self.Num2
    def subtract(self):
        return self.Num1 - self.Num2
    def multiply(self):
        return self.Num1 * self.Num2
    def divide(self):
        return self.Num1 / self.Num2
    def allInOne(self):
            result = {
            "add": self.Num1 + self.Num2,
            "sub": self.Num1 - self.Num2,
            "mult": self.Num1 * self.Num2,
            "div": self.Num1 / self.Num2}
            return result
    def start(self):
        print('which calculation do you want to perform?''\n'
              '1: Add' '\n' '2: Subtract''\n'
              '3: Multiply' '\n' '4: Divide' '\n' '5: allInOne')
        choice = int(input("Enter your choice: "))
        switcher = {1: self.add(),
                2: self.subtract(), 
                3: self.multiply(), 
                4: self.divide(),
                5: self.allInOne()}
        function = switcher.get(choice)
        return function


a = int(input("Enter a number: "))
b = int(input("Enter another number: "))
function = calculator(a,b)
pass
print(function.start())

## 以下是要添加的scalc函数
def scalc(p1):
    # p1 will be a string like this "N1, N2, operator"
    items = p1.split(",")
    operand1 = float(items[0].strip())
    operand2 = float(items[1].strip())
    operator = items[2].strip()
    if operator == "+":
        return sum1(operand1, operand2)
    elif operator == "-":
        return difference1(operand1, operand2)
    elif operator == "*":
        return product1(operand1, operand2)
    elif operator == "/":
        return quotient1(operand1, operand2)

直接把scalc的逻辑改成calculator类的静态方法即可，这样既不用重复定义计算函数，又能把所有计算功能收拢到同一个类里，结构更清晰。修改后的代码如下：

class calculator:
    def __init__(self,a,b):
        self.Num1 = a
        self.Num2 = b
    def add(self):
        return self.Num1 + self.Num2
    def subtract(self):
        return self.Num1 - self.Num2
    def multiply(self):
        return self.Num1 * self.Num2
    def divide(self):
        if self.Num2 == 0:
            return "Error: 除数不能为0"
        return self.Num1 / self.Num2
    def allInOne(self):
            result = {
            "add": self.Num1 + self.Num2,
            "sub": self.Num1 - self.Num2,
            "mult": self.Num1 * self.Num2,
            "div": self.divide() if self.Num2 !=0 else "Error: 除数不能为0"}
            return result
    def start(self):
        print('which calculation do you want to perform?''\n'
              '1: Add' '\n' '2: Subtract''\n'
              '3: Multiply' '\n' '4: Divide' '\n' '5: allInOne')
        choice = int(input("Enter your choice: "))
        # 修复提前执行方法的问题，延迟调用
        switcher = {1: self.add,
                2: self.subtract, 
                3: self.multiply, 
                4: self.divide,
                5: self.allInOne}
        function = switcher.get(choice)
        return function() if function else "无效选择"

    @staticmethod
    def scalc(p1):
        # 解析输入字符串
        items = p1.split(",")
        # 处理格式错误
        if len(items) !=3:
            return "Error: 输入格式错误，请使用'N1, N2, 运算符'格式"
        try:
            operand1 = float(items[0].strip())
            operand2 = float(items[1].strip())
        except ValueError:
            return "Error: 输入的不是有效数字"
        
        operator = items[2].strip()
        # 直接执行运算，避免依赖未定义函数
        if operator == "+":
            return operand1 + operand2
        elif operator == "-":
            return operand1 - operand2
        elif operator == "*":
            return operand1 * operand2
        elif operator == "/":
            if operand2 ==0:
                return "Error: 除数不能为0"
            return operand1 / operand2
        else:
            return f"Error: 不支持的运算符'{operator}'"


# 使用示例
# 原有功能使用
a = int(input("Enter a number: "))
b = int(input("Enter another number: "))
calc = calculator(a,b)
print(calc.start())

# 新增scalc功能使用
input_str = input("输入计算字符串（格式：N1, N2, 运算符）：")
print(calculator.scalc(input_str))

关键修改点说明： #

1. 把scalc改成静态方法，无需实例化就能调用，也可在实例内使用
2. 修复原代码中switcher提前执行所有计算方法的问题，改用延迟调用
3. 添加格式校验和错误处理，避免输入异常导致程序崩溃
4. 移除对未定义sum1、difference1等函数的依赖，直接复用运算逻辑

如果非要单独建类也可行，但完全没必要——所有功能都围绕计算展开，整合在同一个类里更符合代码内聚性原则，维护起来也更方便。

内容的提问来源于stack exchange，提问作者Clown Face