模型状态无效

Question

所以我有一个名为index的视图,它列出了我数据库中的所有线程.然后在该视图中我加载了线程上的所有注释.当我打电话给我应该创建新评论的表单时,它会一直告诉我模型状态无效.它告诉我它无法从类型字符串转换为类型配置文件或注释或标记.最初我把它作为我的代码:

 public ActionResult AddComment(Thread thread, string commentBody)
    {
        if (ModelState.IsValid)
        {
            _repository.AddComment(thread, comment);
            TempData["Message"] = "Your comment was added.";
            return RedirectToAction("Index");
        }

然后我改为:

 public ActionResult AddComment(Thread thread, string commentBody)
    {
        Profile profile = _profileRepository.Profiles.FirstOrDefault(x => x.Id ==       thread.ProfileId);
        Tag tag = _tagRepository.Tags.FirstOrDefault(t => t.Id == thread.TagId);
        thread.ThreadTag = tag;
        thread.Profile = profile;
        Comment comment = new Comment()
                              {
                                  CommentBody = commentBody,
                                  ParentThread = thread
                              };
        if (ModelState.IsValid)
        {
            _repository.AddComment(thread, comment);
            TempData["Message"] = "Your comment was added.";
            return RedirectToAction("Index");
        }

这仍然告诉我模型状态无效.如何获得它以便它不会尝试改变状态？

此处还有用于调用此操作的表单:

@using(Html.BeginForm("AddComment", "Thread", mod))
            {
                <input type="text" name="AddComment" id="text" />
                <input type="submit" value="Save"/>
            }

在上面的代码实例中,mod是一个线程的模型.这里要求的是线程内的所有内容:

 public Thread()
    {
        this.ChildComments = new HashSet<Comment>();
    }

    public int Id { get; set; }
    public string TopicHeader { get; set; }
    public string TopicBody { get; set; }
    public Nullable<int> UpVotes { get; set; }
    public Nullable<int> DownVotes { get; set; }
    public int ProfileId { get; set; }
    public int TagId { get; set; }

    public virtual Profile Profile { get; set; }
    public virtual ICollection<Comment> ChildComments { get; set; }
    public virtual Tag ThreadTag { get; set; }

最后评论类:

 public partial class Comment
{
    public int Id { get; set; }
    public string CommentBody { get; set; }
    public int UpVotes { get; set; }
    public int DownVotes { get; set; }

    public virtual Thread ParentThread { get; set; }
}

Answer 1

使用下面的代码迭代错误.然后,您可以查看哪些字段以及哪些对象在验证时失败.然后你可以从那里去.只是查看IsValid属性不会提供足够的信息.

var errors = ModelState.Values.SelectMany(v => v.Errors);

然后循环错误.