创建一个模型类字段，其中包含来自ASP.NET MVC中另一个表的对象列表

Question

I'm learning C# and ASP.NET MVC Framework from 2 weeks and I would like to apply these knowledges through a small web application. I need your help/advices in order to set a new field between 2 classes.

Objective:

This application should be useful for my soccer team. I have a first CRUD which let to handle players. I can create players, edit players ...

I have a second CRUD which let to handle match details (datetime, pitch, match format ...).

I would like to be able to add available players for a specific match. That is to say, to be able to add a list of players from table Joueur inside a field in the table Match . Through this way, when I look a match in details, I cna see the list of players in order to create the team composition later with JavaScript if it's possible by moving object on a dynamic picture (not my issue for the moment).

My class Joueur :

Very simple:

namespace FCSL.Models.Joueur
{
    public class Joueur
    {
        [Key, Display(Name = "ID")]
        public int JoueurID { get; set; }

        [Required, Display(Name = "Nom"), StringLength(30)]
        public string Lastname { get; set; }

        [Required, Display(Name = "Prénom"), StringLength(30)]
        public string Firstname { get; set; }

        [Required]
        [Display(Name = "Poste")]

        public string Poste { get; set; }

        public string Image { get; set; }

    }
}

I have behind the CRUD generated by Visual Studio which works fine.

My class Match :

namespace FCSL.Models.Match
{
    public class Match
    {
        [Key]
        public int EquipeID { get; set; }

        [Required, Display(Name = "Date du match")]
        [DataType(DataType.Date)]
        [DisplayFormat(DataFormatString = "{0:dd-MM-yyyy}", ApplyFormatInEditMode = true)]
        public DateTime MatchDay { get; set; }

        [Required, Display(Name = "Heure du match")]
        [DataType(DataType.Time)]
        [DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:H:mm}")]
        public DateTime MatchTime { get; set; }

        [Required]
        public string Adversaire { get; set; }

        [Required, Display(Name = "Type de match")]
        public string Format { get; set; }

        [Required]
        public string Terrain { get; set; }

        [Display]
        public string Tresse { get; set; }

        [Required, Display(Name = "Mot-clé")]
        public string Slug { get; set; }
    }
}

Add a new field:

Now I would like a new field in my Match class in order to select list of players from Joueur class in a field named ListeJoueurs .

Do I have to add this something like this ?

[Required, Display(Name = "Joueurs")]
public List<Joueur.Joueur> ListeJoueurs { get; set; }

Then, how I can display a multiple selected dropdown to display this field in my create.cshtml view file ?

Thank you very much by advance

Answer 1

public class Match { all old propertiese publis string ListeJoueurs { get; set; } }

ViewBag.lstCourse=your list;

        @Html.DropDownListFOR(m=>m.ListeJoueurs ,ViewBag.lstCourse as selectectlsist),select"",new { @class = "form-control"})

Answer 2

You need to add two properties TeamOne and TeamTwo and in each team add property Players as collection that hold the selected players for each team.

In your Class Match :

namespace FCSL.Models.Match
{
    public class Match
    {
        ...

        public Team TeamOne { get; set; }
        public Team TeamTwo { get; set; }
    }
}

Add a new class Team :

namespace FCSL.Models.Match
{
    public class Team
    {
        ...

        [Required, Display(Name = "Joueurs")]
        public List<Joueur.Joueur> ListeJoueurs { get; set; }
    }
}

You need also to create a view model instead of sending the model to the view, in your viewmodel you need also to transform your ListJoueurs into MultiSelectList

And you pass your created viewmodel throw a viewbag like below:

public ActionResult Match()
{
    ...
    var match = new MVCApp.Models.Match
    {
        AdversaryTeam = "Equipe de France",
        Field = "Stade de France",
        MatchDay = DateTime.Today,
        MatchTime = DateTime.Now,
        TeamOne = new Team
        {
            Players = new List<Player>
            {
                new Player { PlayerID = 1, Firstname = "Zineeddine", Lastname = "Zidane", Poste = "" },
                new Player { PlayerID = 2, Firstname = "Roberto", Lastname = "Carlos", Poste = "" },
                new Player { PlayerID = 3, Firstname = "Gianluca", Lastname = "Pagliuca", Poste = "" },
            }
        },

         TeamTwo = new Team
         {
            Players = new List<Player>
            {
                new Player { PlayerID = 1, Firstname = "Zineeddine", Lastname = "Zidane", Poste = "" },
                new Player { PlayerID = 2, Firstname = "Roberto", Lastname = "Carlos", Poste = "" },
                new Player { PlayerID = 3, Firstname = "Gianluca", Lastname = "Pagliuca", Poste = "" },
            }
         }
    };

    var vm = new MatchPlayersVM
    {
        Match = match, 
        TeamOnePlayers = match.TeamOne.Players.Select(p => new SelectListItem { Text = p.Firstname, Value = p.PlayerID.ToString() }),
        TeamTwoPlayers = match.TeamTwo.Players.Select(p => new SelectListItem { Text = p.Firstname, Value = p.PlayerID.ToString() }),
    };

    ViewBag.MatchVM = vm;

    return View();
}

Finally in your create.chtml add your dropdown like below:

@using MVCApp.Models

@model MatchPlayersVM

@Html.DropDownListFor(m => m.TeamOneSelectedValues, ViewBag.MatchVM.TeamOnePlayers as IEnumerable<SelectListItem>, new { multiple = "multiple" })

@Html.DropDownListFor(m => m.TeamTwoSelectedValues, ViewBag.MatchVM.TeamOnePlayers as IEnumerable<SelectListItem>, new { multiple = "multiple" })