这段代码对我有用,但我不知道是什么导致了这个错误.我唯一的猜测是,当我尝试创建一个播放器时,团队数据被发送回团队表并尝试重复,但是由于TeamId是唯一的,因此这个错误.
The INSERT statement conflicted with the FOREIGN KEY constraint “FK_dbo.Players_dbo.Teams_TeamId”. The conflict occurred in database “Web”,table “dbo.Teams”,column ‘TeamId’. The statement has been terminated.
播放机
public class Player
{
...
...
[HiddenInput(DisplayValue = false)]
[ForeignKey("Team")]
public int TeamId { get; set; }
public virtual Team Team { get; set; }
...
}
球队
public class Team
{
[Key]
[HiddenInput(DisplayValue = false)]
public int TeamId { get; set; }
....
public virtual ICollection<Player> Players { get; set; }
}
调节器
//
// GET: /Player/
[HttpGet]
public ActionResult Create()
{
PopulateTeamsDropDownList();
return View();
}
//
// POST: /Player/
[HttpPost]
public ActionResult Create(Player model)
{
if (ModelState.IsValid)
{
using (var db = new EfDb())
{
var userProfile = db.UserProfiles.Single(u => u.UserName == User.Identity.Name);
if (userProfile != null)
{
var player = new Player
{
UserProfile = userProfile,....
....
};
db.Players.Add(player);
db.SaveChanges();
}
}
}
PopulateTeamsDropDownList(model.TeamId);
return View(model);
}
private void PopulateTeamsDropDownList(object selectedTeams = null)
{
var teamsQuery = from d in _iService.Teams
orderby d.Name
select d;
ViewBag.TeamID = new SelectList(teamsQuery,"TeamId","Name",selectedTeams);
}
视图
<div class="editor-label">
@Html.LabelFor(model => model.TeamId,"Pick Your Team")
</div>
<div class="editor-field">
@Html.DropDownList("TeamId",String.Empty)
@Html.ValidationMessageFor(model => model.TeamId)
</div>
解决方法
您应该尝试为您的玩家实体完成像团队这样的实体.特别是外键.
[HttpPost]
public ActionResult Create(Player model)
{
if (ModelState.IsValid)
{
using (var db = new EfDb())
{
//Since you have the username cached,you can check the local EF cache for the object before hitting the db.
//var userProfile = db.UserProfiles.Single(u => u.UserName == User.Identity.Name);
var userProfile = db.UserProfiles.Local.SingleOrDefault(u => u.UserName == User.Identity.Name)
?? db.UserProfiles.SingleOrDefault(u => u.UserName == User.Identity.Name);
if (userProfile != null)
{
var player = new Player
{
UserProfile = userProfile,....
....
};
player.TeamId = 5;
db.Players.Add(player);
db.SaveChanges();
}
}
}
PopulateTeamsDropDownList(model.TeamId);
return View(model);
}
并确保您的视图中的“下拉列表”是必需的,并向post方法发送正确的值.
