javascript - 如何在类中设置局部变量

Question

class Calculator {
  constructor() {
    console.log(`Enter the numbers and the operation index you want to perform: 
        1) Addition 
        2) Substraction 
        3) Multiplication 
        4) Division`);

    this.calculate();
  }

  /** 
   * @param {number} firstValue get the first value
   *  @param {number} secondValue get the second value 
   */
  addition(firstValue, secondValue) {
    return firstValue + secondValue;
  }

  /**
   * @param {number} firstValue get the first value
   *  @param {number} secondValue get the second value 
   */
  subtraction(firstValue, secondValue) {
    return firstValue - secondValue;
  }

  /** 
   *  @param {number} firstValue get the first value 
   *  @param {number} secondValue get the second value 
   */
  multiplication(firstValue, secondValue) {
    return firstValue * secondValue;
  }

  /** 
   *  @param {number} firstValue get the first value 
   *  @param {number} secondValue get the second value 
  */
  division(firstValue, secondValue) {
    if (secondValue != 0) {
      return firstValue / secondValue;
    }
    return 'Cannot perform division by 0';
  }

  calculate() {
    prompt.get(propertiesPrompt, (error, values) => {
      if (error) {
        throw new Error(error);
      }

      console.log(operationResult[values.operation](values.valueOne, values.valueTwo));
      prompt.get(choiceResponse, (responseError, response) => {
        if (responseError) {
          throw new Error(responseError);
        }

        if (response.optionSelected.toLowerCase() == 'y') {
          this.calculate()
        }
      });
    });
  }
}

在上面的代码中，我想删除加减乘除方法中的参数，并想在类中设置一个变量属性，以便我可以直接调用方法中存储的值并进行操作。怎么可能做到这一点？

Answer 1

局部类变量的正确名称是字段:

class Calculator {
  constructor() {
    this.field = 10
  }

  show() {
    console.log(this.field)
  }
}

类的函数名称也是一个方法

方法和字段一起是成员