填充导航属性的导航属性 [英] Populating navigation properties of navigation properties

问题描述

如何使用特定值填充导航属性?

How do I populate a navigation property with specific value?

我有3个模型，分别是Game，UserTeam，User，定义如下.我有一个使用IEnumerable模型的剃刀视图.该视图在游戏"上循环，在该循环内，在"UserTeam"上循环.到目前为止，一切都很好.

I have 3 models, Game, UserTeam, User, defined below. I have a razor view which uses the model IEnumerable. This view loops over the Games, and within that loop, loops over the UserTeams. So far, so good.

在UserTeam循环中，我想访问User属性，但它们为null.如何为每个UserTeam对象填充用户导航"属性?我需要在UserTeam模型中使用带参数的构造函数吗?

Within the UserTeam loop, I want to access the User properties, but they are null. How do I populate the User navigation property for each UserTeam object? Do I need a constructor with a parameter in the UserTeam model?

模型

public class Game
{
    public Game()
    {
        UserTeams = new HashSet<UserTeam>();
    }

    public int Id { get; set; }
    public int CreatorId { get; set; }
    public string Name { get; set; }
    public int CurrentOrderPosition { get; set; }

    public virtual UserProfile Creator { get; set; }
    public virtual ICollection<UserTeam> UserTeams { get; set; }
}


 public class UserTeam
{
    public UserTeam()
    {
        User = new UserProfile();
    }

    public int Id { get; set; }
    public int UserId { get; set; }
    public int GameId { get; set; }
    public int OrderPosition { get; set; }

    public virtual UserProfile User { get; set; }
    public virtual Game Game { get; set; }
    public virtual IList<UserTeam_Player> UserTeam_Players { get; set; }

}

public class UserProfile
{
    [Key]
    [DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
    public int UserId { get; set; }
    public string UserName { get; set; }
    public string test { get; set; }

    public UserProfile()
    {
        UserTeams = new HashSet<UserTeam>();
    }

    public virtual ICollection<UserTeam> UserTeams { get; set; }
    [ForeignKey("CreatorId")]
    public virtual ICollection<Game> Games { get; set; }
}

Razor视图中的循环(模型是IEnumerable)

Loop in my Razor view (Model is IEnumerable)

@foreach (var item in Model) {
        @foreach (var userteam in item.UserTeams) {
                        @Html.ActionLink("Join game as"+userteam.User.UserName, "JoinGame", new { gameid = item.Id, userid=userteam.UserId })
        }
}

我的存储库中返回游戏的方法

Method in my repository that returns the Games

public IEnumerable<Game> GetAllGames()
    {
        using (DataContext)
        {
            var gm = DataContext.Games.Include("UserTeams").ToList();
            return gm;
        }
    }

推荐答案

您需要将其包含在存储库方法中.如果您使用的是紧急加载，则应该是

You would need to include this in your repository method. If you are using eager loading then it would be something like

var gm = DataContext.Games
                     .Include(x => x.UserTeams)
                     .Include(x => x.UserTeams.Select(y => y.User))
                     .ToList();

在没有使用LINQ进行查询的情况下，我并没有做到这一点，但是我认为它会是这样的:

I have not done this without using LINQ for my queries, but I assume it would be something like:

var gm = DataContext.Games.Include("UserTeams.User").ToList();

希望这对您有帮助

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