mvc 中的远程验证受影响的编辑

Question

我试图通过客户端的远程验证来验证用户名，并且在创建模块中添加重复字段时它工作正常但现在它不允许我使用相同的名称编辑记录它向我显示相同的错误我为创建定义的。我尝试了所有可能的方法，但没有成功，请帮助我。我已经关注了这些链接，但它不能以任何一种方式工作。

http://stackoverflow.com/questions/4778151/asp-net-mvc-3-remote-validation-to-allow-original-value http://stackoverflow.com/questions/6407096/asp-net-mvc-3-remote-attribute-passing-3-fields

这是我迄今为止尝试过的代码。请帮助专家。

[Required]
        [Remote("IsUserAvailable", "User", HttpMethod = "Post", ErrorMessage = "User already exist.", AdditionalFields = "InitialUserName")]
        [RegularExpression(@"^(?![\W_]+$)(?!\d+$)[a-zA-Z0-9 ]+$", ErrorMessage = "Invalid UserName ")]
 public string UserName { get; set; }


[HttpPost]
    public JsonResult IsUserAvailable([Bind(Prefix = "User.UserName")]string UserName, string initialUserName)
    {

        var result = uDbContext.Users.FirstOrDefault(a => a.UserName == UserName);
        if (result == null)
        {
            return Json(true, JsonRequestBehavior.AllowGet);
        }
        return Json(JsonRequestBehavior.AllowGet);
    }


@model User.ViewModel.ViewModelUser
@using (Html.BeginForm())
    {
        @Html.AntiForgeryToken()
        @Html.ValidationSummary(true)
        @Html.HiddenFor(m => m.User.UserId)



                @Html.LabelFor(m.User.UserName)


               @Html.TextBoxFor(m => m.User.UserName)
                @Html.ValidationMessageFor(m.User.UserName)
                @Html.Hidden("initialUserName", Model.User)
            </div>
        </div>
}

请帮助专家完成我的任务。

Answer 1

User 似乎是一个复杂的对象，所以

@Html.Hidden("initialUserName", Model.User)

可能会产生类似的东西

<input type="hidden" name="initialUserName" value="YourAssemly.User" ... />

这对验证没有帮助。

您可以通过使用发送回原始名称来忽略验证

@Html.Hidden("InitialUserName", Model.User.UserName)

@Html.Hidden("User.InitialUserName", Model.User.UserName)

然后使用比较控制器中的值

public JsonResult IsUserAvailable([Bind(Prefix = "User.UserName")]string UserName, string initialUserName)

public JsonResult IsUserAvailable([Bind(Prefix = "User.UserName")]string UserName, [Bind(Prefix = "User.InitialUserName")]string initialUserName)
{
  if (UserName == initialUserName)
  {
    // Nothing has changed so signal its valid
    return Json(true, JsonRequestBehavior.AllowGet);
  }
  // Check if the user name already exists
  var result = uDbContext.Users.FirstOrDefault(a => a.UserName == UserName);
  return Json(result == null, JsonRequestBehavior.AllowGet);
}

旁注：jquery 远程验证是一个 GET 调用，因此不需要 [HttpPost] 属性

编辑

在调试jquery-validate.js 和jquery-validate-unobtrusive.js 文件后，发现任何AdditionalFields 的name 属性必须包含与正在验证的属性相同的前缀，并且[Bind(Prefix="..")] 属性也是必需的方法中的那些参数（参考上面的修改）

另一种方法可能是创建一个简单的类来回发，例如

public class ValidateUserNameVM
{
  public string UserName { get; set; }
  public string InitialUserName { get; set; }
}

和

public JsonResult IsUserAvailable([Bind(Prefix = "User")]ValidateUserNameVM model)
{
  if (model.UserName == model.InitialUserName)
  ....

Answer 2

您的验证功能不完整。将[Required] 属性放在模型的UserName 属性上，然后试试这个：

public JsonResult IsUserAvailable(string userName, string initialUserName)
{
   if (userName.Trim().ToLower() != (initialUserName ?? "").Trim().ToLower())
   {
       var result = YourMethodToCheckTheDatabaseForUsernameIsAvailable(userName);
       return Json(result, JsonRequestBehavior.AllowGet);
   }
   return Json(true, JsonRequestBehavior.AllowGet);
}

Answer 3

对于在第二个参数中获取 Null 的人来说，这个简单的想法可能会有所帮助

public JsonResult IsUserNameAvailable(string Name, string EditNameIssue)
        {//it will return true if match found elese it will return false. so i add !
            if (Name == EditNameIssue)
            {
                return Json(true, JsonRequestBehavior.AllowGet);
            }
            else
            {
                return Json(!db.Employees.Any(e => e.Name == Name), JsonRequestBehavior.AllowGet);
            }
        }

转到班级并将string EditNameIssue 添加到班级，以便可以将其发送到控制器

[MetadataType(typeof(EmployeeMetaData))]
    public partial class Employee
    {

        public string EditNameIssue { get; set; }
    }

并编辑 Remote 属性以发送此附加属性

[Remote("IsUserNameAvailable","Employees",ErrorMessage ="User Name Already Taken",AdditionalFields = "EditNameIssue")]
        public string Name { get; set; }

如果您添加名称以编辑已被占用的文本框，此逻辑可能会有所帮助

public JsonResult IsUserNameAvailable(string Name, string EditNameIssue)
    {//it will return true if match found elese it will return false. so i add !
        //Edit Request  
        if (Name == EditNameIssue)
        {
            //this mean he didn't change the name
            return Json(true, JsonRequestBehavior.AllowGet);
        }
        else if (Name != EditNameIssue)
        {
            //if he change the name in the edit go and check if the new name exist 
            //note if he modify and reenter it origin name it will be also erro he has to reload
            return Json(!db.Employees.Any(e => e.Name == Name), JsonRequestBehavior.AllowGet);
        }
        else if (string.IsNullOrEmpty(EditNameIssue))
        {//this mean you came from create request as there is no EditNameIssue in this view

            return Json(!db.Employees.Any(e => e.Name == Name), JsonRequestBehavior.AllowGet);

        }
        else
        {//just for the completeness
            return Json(false, JsonRequestBehavior.AllowGet);
        }


    }