Question

我正在创建一个简单的博客。当用户向特定条目添加评论时，发出发布请求时，评论详细信息未绑定？

当我抛出一个断点和post方法时，所有带有“红十字标志”并指出 “隐式函数评估已由用户关闭”的参数 。

这里是所有代码。

控制器

using Blog.Models;
using Blog.ViewModels;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Data.Entity;

namespace Blog.Controllers
{
    public class CommentsController : Controller
    {
        private ApplicationDbContext _context;
        public CommentsController()
        {
            _context = new ApplicationDbContext();
        }

        // GET: Comments
        public ActionResult Index(int entryId)
        {
            Entry entryFromDb = _context.Entries.Include(c => c.Category).Single(e => e.Id == entryId);

            EntryAndCommentViewModel viewModel = new EntryAndCommentViewModel()
            {
                entry = entryFromDb,
                EntryId = entryId
            };
            return View("CommentForm",viewModel);
        }

        [HttpPost]
        public ActionResult Save(Comment comment)
        {

            Entry entryFromDb = _context.Entries.Include(c => c.Category).Single(e => e.Id == comment.EntryId);
            if (!ModelState.IsValid)
            {

                EntryAndCommentViewModel _viewModel = new EntryAndCommentViewModel()
                {
                    entry = entryFromDb,
                    EntryId = comment.EntryId
                };
                return View("CommentForm", _viewModel);
            }

            return View();
        }
    }
}

ViewModel

using Blog.Models;
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;

namespace Blog.ViewModels
{
    public class EntryAndCommentViewModel
    {
        [Required]
        public int EntryId { get; set; }
        public Entry entry { get; set; }

        [Required]
        [StringLength(50)]
        public string Name { get; set; }

        [Required]
        [StringLength(100)]
        [EmailAddress]
        public string EmailAddress { get; set; }

        [Required]
        [StringLength(1000)]
        public string CommentDetails { get; set; }

    }
}

查看

@model Blog.ViewModels.EntryAndCommentViewModel
@{
    ViewBag.Title = "CommentForm";
}

<br />

<p class="alert alert-danger">Add <b>Comment</b> to this Post.</p>

<h3>
    <b>
        @Model.entry.Subject
    </b>
</h3>
<p>
    <i>
        Category : <b>@Model.entry.Category.Name</b> - Posted on @Model.entry.PostDate.ToString("dd MMM yyyy")
    </i>
</p>
<p>
    @Model.entry.Body
</p>

<P>
    (0) Comments
</P>

<br />

<h2>Leave a Comment</h2>
<br />
@using (Html.BeginForm("Save", "Comments"))
{
    @Html.HiddenFor(m => m.entry.Id)
    <div class="form-group">
        @Html.LabelFor(m => m.Name)
        @Html.TextBoxFor(m => m.Name, new { @class = "form-control", autofocus = "autofocus", Placeholder = "e.g James Anderson" })
        @Html.ValidationMessageFor(m => m.Name)
    </div>

    <div class="form-group">
        @Html.LabelFor(m => m.EmailAddress)
        @Html.TextBoxFor(m => m.EmailAddress, new { @class = "form-control", Placeholder = "e.g YourEmail@Domain.com" })
        @Html.ValidationMessageFor(m => m.EmailAddress)
    </div>

    <div class="form-group">
        @Html.LabelFor(m => m.CommentDetails)
        @Html.TextAreaFor(m => m.CommentDetails, 4, 8, new { @class = "form-control", Placeholder = "e.g Comment description goes here!" })
        @Html.ValidationMessageFor(m => m.CommentDetails)
    </div>
    <button type="submit" class="btn btn-primary">Save</button>
    <button type="reset" class="btn btn-link">Reset</button>

}

如何解决？谢谢

Answer 1

打开或关闭自动属性评估

在“工具”菜单上，单击“选项”。在“选项”对话框中，打开“调试”节点，然后单击“常规”。如果未出现“调试”节点，请单击“显示所有设置”。选择或清除“启用属性评估和其他隐式函数调用”复选框，然后单击“确定”

隐式Model Binder无法在MVC中工作？

1 个答案: