c# - CS1061 C# 'Player' 不包含定义，并且找不到接受“Player”类型的第一个参数的可访问扩展方法

Question

我对 C# 和 Visual Studio 比较陌生，并且一直在关注作业中的工作表，我逐行关注它，但发现了 2 个与同一问题相关的错误，并且无法构建和运行它，直到它们被修复。任何帮助将不胜感激

错误是该行中标记为粗体和斜体的第二个俱乐部：
Clubs = b.Clubs.Select(a => new ClubDTO()

// GET: api/Players/5
[ResponseType(typeof(PlayerDTO))]
public async Task<IHttpActionResult> GetPlayer(int id)
{
    Player b = await db.Players.FindAsync(id);
    if (b == null)
    {
        return NotFound();
    }
    PlayerDTO player = new PlayerDTO
    {
        PlayerId = b.PlayerId,
        Name = b.Name,
        Position = b.Position,
        Goals = b.Goals,
        Clubs = b.Clubs.Select(a => new ClubDTO()
        {
            ClubId = a.ClubId,
            TeamName = a.TeamName,
            Country = a.Country,
            League = a.League
        }

                      ).ToList()
    };
    return Ok(player);
}

玩家：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace Project.Models
{
    public class Player
    {
        private ICollection<Club> _clubs;
        public int PlayerId { get; set; }
        public string Name { get; set; }
        public string Position { get; set; }
        public int Goals { get; set; }

        public virtual List<Club> Clubs
        {
            get { return _clubs.ToList(); }
            set { _clubs = value; }
        }



    }
}

PlayerDTO

    
    namespace Project.Models
    {
        public class PlayerDTO
        {
            public int PlayerId { get; set; }
            public string Name { get; set; }
            public string Position { get; set; }
            public int Goals { get; set; }
            public List<ClubDTO> Clubs { get; set; }
        }
    }

标签： c#.netunity3d