C# 中的 Inheritance 问题：CS7036

Question

出于某种原因，我在构造函数方法“ModifiedExercise”CS7036 中遇到错误：没有给出与所需的形式参数name对应的参数。Exercise Exercise.Exercise(string,int,int,string,string[],Dictionary<string,bool>)我添加了 Parent 和 child 类Exercise和ModifiedExercise 。

using System;
using System.Collections.Generic;
using System.Text;

namespace Trainer_App
{
    internal class ModifiedExercise : Exercise 
    {
        private Exercise regular_exercise;
        public ModifiedExercise(Exercise regular_exercise,
                                string name,
                                int min_num_balls,
                                int participants_num,
                                string court_type,
                                string[] accessories,
                                Dictionary<string, bool> exerciseTypes)
        {
            this.regular_exercise = regular_exercise;
            this.id = Exercise.id_counter;
            Exercise.id_counter++;
            this.name = name;
            this.min_num_balls = min_num_balls;
            this.participants_num = participants_num;
            this.court_type = court_type;
            this.accessories = accessories;
            this.exerciseTypes = exerciseTypes;

        }
    }
}

---

using System;
using System.Collections.Generic;
using System.Text;

namespace Trainer_App
{
    internal class Exercise
    {
        protected static int id_counter = 0;
        protected int id;
        protected string name;
        protected int min_num_balls;
        protected int participants_num;
        protected string court_type;
        protected string[] accessories;
        protected static int exerciseCounter = 0;
        protected Dictionary<string, bool> exerciseTypes = new Dictionary<string, bool>();

        public Exercise(string name,int min_num_balls, int participants_num,string court_type, string[]accessories,Dictionary<string,bool> exerciseTypes)
        {
            this.id = id_counter;
            id_counter++;
            this.name = name;
            this.min_num_balls = min_num_balls;
            this.participants_num = participants_num;
            this.court_type = court_type;
            this.accessories = accessories;
            this.exerciseTypes = exerciseTypes;
        }



    }
}

Answer 1

默认情况下，构造函数在其基本类型上有效地调用: base()

您在这里有两个选择：

1. 将protected Exercise(){}无参数构造函数添加到基类型
2. 添加显式: base(...)显式指定将哪个值传递到哪个 position 到基本构造函数

注：2是通常的做法，减少重复。 这也允许字段保持private 。