c# - 使用 Entity Framework 5 错误和 DbUpdateConcurrencyException 更新记录

Question

在 MVC 3 Entity Framework 项目中，我似乎在追逐自己的尾部，没有得到要更新的简单记录，这让我发疯了。我错过了什么？

我可以很好地创建记录，但似乎无法计算出执行更新的逻辑。我尝试了多种方法，附加，不附加，并且我认为在涉及外键或其他内容时我错过了一种模式。

View 返回的对象已完全填充且模型有效。填充了外键 ID 字段。

请有任何想法。

POCO 是

public class EFormApplication
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int ApplicationId { get; set; }
    [ForeignKey("ApplicationTemplateId")]
    public virtual ApplicationTemplate ApplicationTemplate { get; set; }
    public int ApplicationTemplateId { get; set; }
    [Required(ErrorMessage = "Each application must have a Title")]
    public string Title { get; set; }
    [Required(ErrorMessage = "Each application must have a Description. This is visible to the clients")]
    public string Description { get; set; }
    [ForeignKey("SecurityId")]
    public virtual Security Security { get; set; }
    public int SecurityId { get; set; }
    public bool Published { get; set; }
    [Display(Name = "EIDV Required")]
    public bool EIDVRequired { get; set; }
    [Display(Name = "Investor confirmation required")]
    public bool InvestorConfirmationRequired { get; set; }
    [Display(Name = "Advisor confirmation required")]
    public bool AdvisorConfirmationRequired { get; set; }
    [Display(Name = "Payment required")]
    public bool PaymentRequired { get; set; }
    [Display(Name = "Login Required")]
    public bool UserLoginRequired { get; set; }
    [Display(Name = "ISA Trans allowed")]
    public bool IsaTransfersAllowed { get; set; }
    public DateTime? Deadline { get; set; }
    [Display(Name = "Fully Subscribed")]
    public bool FullySubscribed { get; set; }
    [Display(Name = "Image Url")]
    [RegularExpression(@"^(ht)tp(s?):\/\/[0-9a-zA-Z].+$", ErrorMessage = "You must enter a valid URI including the http:// or https://")]
    public string ImageUrl { get; set; }
    [Display(Name = "Information Url")]
    [RegularExpression(@"^(ht)tp(s?):\/\/[0-9a-zA-Z].+$", ErrorMessage = "You must enter a valid URI including the http:// or https://")]
    public string InformationUrl { get; set; }
    public bool Discontinued { get; set; }
    public DateTime Created { get; set; }
    public string CreatedBy { get; set; }
    public DateTime LastUpdated { get; set; }
    public string LastUpdatedBy { get; set; }

    //navigation
    public virtual ICollection<ApplicationSubmission> ApplicationSubmissions { get; set; }
}

Edit Controller 方法是

    [Authorize(Roles = "Admins")]
    public ActionResult Edit(int applicationId)
    {
        EFormApplication eformapplication = _formRepository.GetEFormApplication(applicationId);
        return View(eformapplication);
    }


    [Authorize(Roles = "Admins")]
    [HttpPost]
    public ActionResult Edit(EFormApplication eformapplication)
    {
        if (ModelState.IsValid)
        {
            eformapplication.LastUpdated = DateTime.UtcNow;
            eformapplication.LastUpdatedBy = User.Identity.Name;

            var opstatus = _formRepository.UpdateEFormApplication(eformapplication);

            if (opstatus.Status)
            {
                return RedirectToAction("Design", "eForm");
            }
            else
            {
                return RedirectToAction("OpStatusError", "Error", opstatus);
            }
        }

        return View(eformapplication);
    }

存储库方法UpdateEFormApplication是保存记录的位，如下所示:

    public OperationStatus UpdateEFormApplication(EFormApplication eFormApplication)
    {
        DataContext.Entry(eFormApplication).State = EntityState.Modified;
        DataContext.SaveChanges();

        return Save(eFormApplication);
    }

Answer 1

当我写这个问题并检查我的事实时，我发现了我犯的一个非常简单的错误!

我忘记在编辑页面上包含 ID 字段，所以在发布的模型中它被设置为零!

教训是......确保所有字段都在表单上表示，如果您不想显示它，则将其作为隐藏字段!

感谢您对 Stack Overflow 的帮助；-)