Question

我的删除操作有问题，我遇到了这个例外：

类型的第一次机会异常   发生'System.Data.Entity.Infrastructure.DbUpdateException'   EntityFramework.dll

其他信息：'Model1Container.PublicationSet'中的实体   参加'PublicationQuartier'的关系。 0相关   发现'Quartier'。预计1'Quartier'。

这是我的删除操作：

        [HttpPost]
    public ActionResult DeleteOffreLocation(int id, OffreLocation offreLocation)
    {
        try
        {
            db.Entry(offreLocation).State = System.Data.Entity.EntityState.Deleted;
            db.SaveChanges();

            return RedirectToAction("ListOffreLocation");
        }
        catch
        {
            return View();
        }
    }

“OffreLocation”型号：

public partial class OffreLocation : Publication
{
    public OffreLocation()
    {
        this.Locataire = new HashSet<Locataire>();
        this.DemandeLocation = new HashSet<DemandeLocation>();
        this.DemandeLocation1 = new HashSet<DemandeLocation>();
        this.DemandeLocation2 = new HashSet<DemandeLocation>();
        this.DemandeLocation3 = new HashSet<DemandeLocation>();
    }

    public string OffreLocation_TypeLog { get; set; }
    public string OffreLocation_Sante { get; set; }
    public double OffreLocation_Loyer { get; set; }
    public System.DateTime OffreLocation_DateDisponibilite { get; set; }
    public double OffreLocation_Superficie { get; set; }
    public short OffreLocation_NbreChambre { get; set; }
    public short OffreLocation_NbrePieces { get; set; }

    public virtual ICollection<Locataire> Locataire { get; set; }
    public virtual Proprietaire Proprietaire { get; set; }
    public virtual ICollection<DemandeLocation> DemandeLocation { get; set; }
    public virtual ICollection<DemandeLocation> DemandeLocation1 { get; set; }
    public virtual ICollection<DemandeLocation> DemandeLocation2 { get; set; }
    public virtual ICollection<DemandeLocation> DemandeLocation3 { get; set; }
}

“出版”模型：

 public partial class Publication
{
    public Publication()
    {
        this.Photo = new HashSet<Photo>();
    }

    public int Publication_ID { get; set; }
    public string Publication_Statut { get; set; }
    public bool Publication_Meublee { get; set; }
    public string Publication_Descriptif { get; set; }
    public bool Publication_ContactParAgence { get; set; }
    public double Publication_Maps_Latitude { get; set; }
    public double Publication_Maps_Longitude { get; set; }

    public virtual Quartier Quartier { get; set; }
    public virtual ICollection<Photo> Photo { get; set; }
}

最后我的数据库容器：

 public partial class Model1Container : DbContext
{
    public Model1Container()
        : base("name=Model1Container")
    {
    }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        throw new UnintentionalCodeFirstException();
    }

    public DbSet<Utilisateur> UtilisateurSet { get; set; }
    public DbSet<Abonnement> AbonnementSet { get; set; }
    public DbSet<AbonnementHistorique> AbonnementHistoriqueSet { get; set; }
    public DbSet<ColocataireIdeal> ColocataireIdealSet { get; set; }
    public DbSet<Publication> PublicationSet { get; set; }
    public DbSet<Quartier> QuartierSet { get; set; }
    public DbSet<Ville> VilleSet { get; set; }
    public DbSet<RegionProvince> RegionProvinceSet { get; set; }
    public DbSet<Photo> PhotoSet { get; set; }
    public DbSet<MessageLocation> MessageLocationSet { get; set; }
    public DbSet<MessageColocation> MessageColocationSet { get; set; }

    public System.Data.Entity.DbSet<COM.MENNILIK.Models.Locataire> Locataires { get; set; }

    public System.Data.Entity.DbSet<COM.MENNILIK.Models.OffreLocation> OffreLocations { get; set; }
}

Answer 1

实际上你需要删除传递给视图的对象。您可以使用id或您的模型OffreLocation。我将以id为例给你一个例子。

 [HttpPost]
public ActionResult DeleteOffreLocation(int id, OffreLocation offreLocation)
{
    try
    {
        var offreLocationGetById =db.OffreLocations.Find(id);
        if(offreLocationGetById!=null)
        db.OffreLocations.Remove(offreLocationGetById);

        db.SaveChanges();

        return RedirectToAction("ListOffreLocation");
    }
    catch
    {
        return View();
    }
}

我建议您在OnModelCreating使用FluentApi代码时对Exception进行评论，然后在旁边抛出{{1}}。这是一个建议。

Answer 2

它似乎是模型验证错误。我非常确定Quartier是必需的，在你的Action的offreLocation中，Quartier应为null。

所以你必须：

填充Quartier或
禁用验证。

使用DB上下文在asp.net MVC中删除Action

2 个答案: