C#正确实现Equals方法,如何实现GetHashCode方法

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Crystal_Message
{
    class Person
    {
        private string firstName ="";
        private string lastName= "";
        private string phone="";


        public Person(string firstName,string lastName,string phone)
        {
            this.FirstName = firstName;
            this.LastName = lastName;
            this.PhoneNumber = phone;
        }

        public string FirstName
        {
            get { return firstName; }

            private set
            {
                if (string.IsNullOrWhiteSpace(value)){

                    throw new ArgumentNullException("Must Include First Name");
                }

                this.firstName = value;
            }

        }

        public string LastName
        {
            get { return lastName; }

            private set
            {
                if (string.IsNullOrWhiteSpace(value)){

                    throw new ArgumentNullException("Must Include Last Name");
                }

                this.lastName = value;
            }

        }

        public string PhoneNumber
        {
            get { return phone; }

            private set
            {
                if (string.IsNullOrWhiteSpace(value)){

                    throw new ArgumentNullException("Must Include Phone Number");
                }

                this.phone = value;
            }

        }


        public override string ToString()
        {
            return "First Name: " + this.FirstName + " " + " Last Name: " + this.LastName + " " + " Phone Number: " + this.PhoneNumber;
        }

        public override bool Equals(object obj)
        {
            if(obj == null)
            {
                return false;
            }

            Person testEquals = obj as Person;

            if((System.Object)testEquals == null)
            {
                return false;
            }

            return (this.firstName == testEquals.firstName) && (this.lastName == testEquals.lastName) && (this.phone == testEquals.phone);   

        }

        /*
        public override int GetHashCode()
        {
           return 
        }
        */ 
    }
}

我在MSDN之前遵循了这些指导原则.两个问题:

>我是否正确实施了equals方法?@H_502_7@>有人能告诉我如何正确地为我的班级实现GetHashCode吗? MSDN做x ^ y,但我不能为我做.

解决方法

好吧,为了不遇到任何问题,GetHashCode应该使用Equals使用的所有成员,反之亦然.

所以在你的情况下:

public override int GetHashCode()
{
    return firstName.GetHashCode() ^ lastName.GetHashCode() ^ phone.GetHashCode();
}

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