.net core 2.1 验证状态：无效

Question

以下简单的 .NET Core 2.1 MVC 代码在我提交创建时报告“验证状态：无效”。没有 Owner 财产一切正常；如果不需要 Owner 属性，它就可以工作。

所有者是服务器端上下文中的当前用户，不应从客户端提交，因此 Create.cshtml 在表单中没有所有者输入。

错误：

info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[1]
      Executing action method AnnouncementApp.Controllers.AnnouncementsController.Create (AnnouncementApp) with arguments (AnnouncementApp.Models.Announcement) - Validation state: Invalid

型号：

using System;
using Microsoft.AspNetCore.Mvc;
using System.ComponentModel.DataAnnotations;
using Microsoft.AspNetCore.Mvc.ModelBinding;
using AnnouncementApp.Models.Attributes;
using Microsoft.AspNetCore.Identity;
//using System.Security.Claims;

namespace AnnouncementApp.Models
{
    public class Announcement
    {   
        public int ID { get; set; }
        [Required]
        public string Content { get; set; }
        [Display(Name = "Start Date and Time")]
        public DateTime StartDate { get; set; }

        [StartEndDate("End Date and Time must be after Start Date and Time")]
        [Display(Name = "End Date and Time")]
        public DateTime EndDate { get; set; }

        [Required]
        [BindNever]
        public IdentityUser Owner { get; set; }
    }   
}

控制器方法：

    [HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Create([Bind("ID,Content,StartDate,EndDate")] Announcement announcement)
    {
        if (ModelState.IsValid)
        {
            var user = await _userManager.GetUserAsync(this.User);
            announcement.Owner = user;
            _context.Add(announcement);
            await _context.SaveChangesAsync();
            return RedirectToAction(nameof(Index));
        }
        return View(announcement);
    }

Create.cshtml

@model AnnouncementApp.Models.Announcement

@{
    ViewData["Title"] = "Create";
}

<h2>Create</h2>

<h4>Announcement</h4>
<hr />
<div class="row">
    <div class="col-md-4">
        <form asp-action="Create">
            <div asp-validation-summary="ModelOnly" class="text-danger"></div>
            <div class="form-group">
                <label asp-for="Content" class="control-label"></label>
                <textarea asp-for="Content" class="form-control"></textarea>
                <span asp-validation-for="Content" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="StartDate" class="control-label"></label>
                <input asp-for="StartDate" class="form-control" />
                <span asp-validation-for="StartDate" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="EndDate" class="control-label"></label>
                <input asp-for="EndDate" class="form-control" />
                <span asp-validation-for="EndDate" class="text-danger"></span>
            </div>
            <div class="form-group">
                <input type="submit" value="Create" class="btn btn-default" />
            </div>
        </form>
    </div>
</div>

<div>
    <a asp-action="Index">Back to List</a>
</div>

@section Scripts {
    @{await Html.RenderPartialAsync("_ValidationScriptsPartial");}
}

Answer 1

对于Announcement，它将为客户端验证和数据库表应用[Required]。

正如 cmets 所示，您可以考虑将 Announcement 拆分为 Db 模型和 ViewModel，您可以定义一个新的 AnnouncementViewModel 用于客户端验证。

对于另一个选项，您可以尝试在 fluent api 中配置 [Required] 而不是属性。

以下是详细步骤。

1. 更改Announcement

   public class Announcement
   {
   public int ID { get; set; }
   [Required]
   public string Content { get; set; }
   [Display(Name = "Start Date and Time")]
   public DateTime StartDate { get; set; }
   public string OwnerId { get; set; }
   //[Required]
   [BindNever]
   [ForeignKey("OwnerId")]
   public IdentityUser Owner { get; set; }
   }
   

2. ApplicationDbContext 中流利的 api

       protected override void OnModelCreating(ModelBuilder builder)
   {
       base.OnModelCreating(builder);
   
       builder.Entity<Announcement>()
              .Property(a => a.OwnerId)
              .IsRequired();           
   }
   

3. 控制器

       [HttpPost]
   [ValidateAntiForgeryToken]
   public async Task<IActionResult> Create([Bind("ID,Content,StartDate")] Announcement announcement)
   {
       if (ModelState.IsValid)
       {
           var user = await _userManager.GetUserAsync(User);
           announcement.Owner = user;
           _context.Add(announcement);
           await _context.SaveChangesAsync();
           return RedirectToAction(nameof(Index));
       }
       return View(announcement);
   }
   

Answer 2

我不是 100% 确定，您定义的问题是什么，但是如果您想抑制“模型无效”错误，因为您总是通过 HttpContext 设置 Owner 属性，您可以在验证之前使用以下内容型号：

ModelState["Owner"].ValidationState = ModelValidationState.Valid

我认为您的问题是您告诉路由器永远不要绑定“所有者”，但您仍然告诉它是必需的，因此 ModelState 可能会使它无效。

只要使用了“Required”注解，我认为如果没有正确设置 ModelState 就不会验证。

例子：

ModelState["Owner"].ValidationState = ModelValidationState.Valid
if (ModelState.IsValid)
        {
            var user = await _userManager.GetUserAsync(this.User);
            announcement.Owner = user;
            _context.Add(announcement);
            await _context.SaveChangesAsync();
            return RedirectToAction(nameof(Index));
        }
        return View(announcement);