c# - 如何从其 ID 中获取对象名称？

Question

我有一个用于对象调用的类Person。Person 类包含值 Name、Last_Name、Age 和最重要的 ID。

如何使用 ID 获取姓名或年龄等信息？代码：

// Person Class    
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

    class Person
    {
        private static int currentID;
        protected int Age { get; set; }
        protected string Name { get; set; }
        protected string Name_Last { get; set; }
        protected int ID { get; set; }
        protected bool Teenager { get; set; }
        public Person()
        {
            Name = "Default";
            Name_Last = "Default";
            ID = GetNextID();
            Age = 0;
        }
        public Person(string name, int age)
        {
            this.Name = name;
            this.Name_Last = Name_Last;
            this.ID = GetNextID();
        }
        static Person()
        {
            currentID = 0;
        }
        protected int GetNextID()
        {
            return ++currentID;
        }
        public void Update(string name, int age, string LastName = "Default")
        {
            this.Name = name;
            this.Name_Last = LastName;
            this.Age = age;
        }
        public override string ToString()
        {
            return String.Format("Name: {0},"+getIsLastNameDiscription(" Lastname: ", ",")+" Age: {1}, isTeenager: "+isTeenager()+", CurrentID: {2}", this.Name, this.Age, this.ID);
        }
        private bool isLastname()
        {
            if (this.Name_Last != "Default")
                return true;
            else
                return false;
        }
        private string getIsLastName()
        {
            if (this.isLastname())
                return this.Name_Last;
            else
                return "";
        }
        private string getIsLastNameDiscription(string Stuffix = "", string EndStuffix = "")
        {
            if (this.isLastname())
                return Stuffix+this.Name_Last+EndStuffix;
            else
                return "";
        }
        public string getIsTeenager(string TrueOutput = "true", string FalseOutput = "false")
        {
            if (this.isTeenager())
                return TrueOutput;
            else
                return FalseOutput;
        }
        public bool isTeenager()
        {
        if(this.Age >= 13 && Age <= 18)
        return true;
        else
        return false;
        }
        public string Discription()
        {
            return String.Format("{0} is {1} years old and he has the ID of {2}", this.Name,
                                                                                  this.Age,
                                                                                  this.ID);
        }
    }

---

// Program Class
class Program : Person
{
    static void Main(string[] args)
    {
        Person Luke = new Person();
        Luke.Update("Luke", 15);
        Console.WriteLine(Luke.ToString());
        Person Daniel = new Person();
        Daniel.Update("Daniel", 14, "Jones");
        Console.WriteLine(Daniel.ToString());
        Person Aimee = new Person();
        Aimee.Update("Aimee", 18, "Jones");
        Console.WriteLine(Aimee.ToString());
        Person Will = new Person();
        Will.Update("William", 22, "Rae");
        Console.WriteLine(Will.ToString());

        Console.ReadLine();
    }
}

Answer 1

将您的Person对象添加到 List 并list使用 id 从该获取对象

Answer 2

public class PersonRepo
{
    static Dictionary<int, Person> people = new Dictionary<int, Person>();
    public void Upsert(Person P)
    {
        if (people.ContainsKey(P.ID))
            people[P.ID] = P;
        else
            people.Add(P.ID, P);
    }

    public Person Get(int ID)
    {
        if (!people.ContainsKey(ID))
            return null;

        return people[ID];
    }
}

然后在你的主要功能中你做

public static void Main()
{
    var people = new PersonRepo()

    Person Luke = new Person();
    Luke.Update("Luke", 15);
    people.Upsert(Luke.ID,Luke);


    Person Daniel = new Person();
    Daniel.Update("Daniel", 14, "Jones");
    people.Upsert(Daniel.ID,Daniel);


    Person Aimee = new Person();
    Aimee.Update("Aimee", 18, "Jones");
    people.Upsert(Daniel.ID,Daniel);


    Person Will = new Person();
    Will.Update("William", 22, "Rae");
    people.Upsert(Daniel.ID,Daniel);

    // To get the person by id you can do
    int id = 3;
    var person = people.Get(id)
    Console.WriteLine(person.ToString())

}   

这还没有看到编译器，所以请原谅任何错别字

Answer 3

您需要存储所有人，例如：

class Program
{
    static List<Person> persons = new List<Person>();
    static void Main(string[] args)
    {


        Person Luke = new Person();
        Luke.Update("Luke", 15);
        Console.WriteLine(Luke.ToString());
        Person Daniel = new Person();
        Daniel.Update("Daniel", 14, "Jones");
        Console.WriteLine(Daniel.ToString());
        Person Aimee = new Person();
        Aimee.Update("Aimee", 18, "Jones");
        Console.WriteLine(Aimee.ToString());
        Person Will = new Person();
        Will.Update("William", 22, "Rae");
        Console.WriteLine(Will.ToString());

        persons.Add(Luke);
        persons.Add(Daniel );
        persons.Add(Aimee );
        persons.Add(Will );

        var founded = FindPersonById("xxx-x-xxxxx");

        Console.ReadLine();
    }  
    static Person FindPersonById(int Id)
    {
        return persons.FirstOrDefault(p => p.ID == Id);
    }
}