Question

发布表单后，我的模型（CountryContinentModels）始终为null。在我的控制器中，我总是得到模型null，我似乎无法找到原因，我已经多次查看了代码，询问了我的班级伙伴并检查了其他几个堆栈溢出问题＆amp;答案，大多数时候问题与命名有关，我不认为这是这种情况。我正在尝试使用CountryContinent模型（包含Country and Continent）在我的数据库中创建一个新条目

我正在设置一个CRUD，而且我很难设置Create。

这是创建视图：

    @model TransactionImporter.WebUI.Models.CountryContinentModels

    @{
    ViewBag.Title = "Create";
    }

    <h2>Create</h2>


    @using (Html.BeginForm()) 
    {
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        <h4>CountryContinentModels</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        <div class="form-group">
            @Html.LabelFor(model => model.Country, new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Country, new { htmlAttributes = new { @class = "form-control" } })
            </div>
        </div>
        <div class="form-group">
            @Html.LabelFor(model => model.Continent, new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Continent, new { htmlAttributes = new { @class = "form-control" } })
            </div>
        </div>
            <div class="col-md-offset-2 col-md-10">
                <input type="submit" value="Create" class="btn btn-default"/>
            </div>
        </div>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>

@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}

这是控制器：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using TransactionImporter.BLL.Interfaces;
using TransactionImporter.Factory;
using TransactionImporter.WebUI.Models;
using TransactionImpoter.Domain;

namespace TransactionImporter.WebUI.Controllers
{
    public class CountryContinentController : Controller
    {
        private ICountryContinentLogic countryContinentLogic = CountryContinentFactory.CreateLogic();

        // GET: CountryContinent/Create
        public ActionResult Create()
        {
            return View();
        }

        // POST: CountryContinent/Create
        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Create(CountryContinentModels models)
        {
            if (ModelState.IsValid)
            {
                CountryContinent countryContinent = new CountryContinent(models.Country, models.Continent);
                countryContinentLogic.AddCountry(countryContinent);

                return RedirectToAction("Index");
            }
            else
            {
                return View();
            }
        }

        // GET: CountryContinent
        public ActionResult Index()
        {
            List<CountryContinent> countryContinents = countryContinentLogic.GetAllCountries();
            List<CountryContinentModels> countryModels = new List<CountryContinentModels>();
            foreach (CountryContinent country in countryContinents)
            {
                countryModels.Add(new CountryContinentModels(country.Country, country.Continent));
            }

            return View(countryModels);
        }


        // GET: CountryContinent/Edit/5
        public ActionResult Edit(int id)
        {
            CountryContinent country = new CountryContinent(countryContinentLogic.GetCountryById(id).Country,
                countryContinentLogic.GetCountryById(id).Continent);
            CountryContinentModels model = new CountryContinentModels(country.Country, country.Continent);
            return View(model);
        }

        // POST: CountryContinent/Edit/5
        [HttpPost]
        public ActionResult Edit(CountryContinentModels model, int id, FormCollection collection)
        {
            try
            {
                CountryContinent continent = new CountryContinent(model.Country, model.Continent);
                countryContinentLogic.UpdateCountryById(id, continent);

                return RedirectToAction("Index");
            }
            catch
            {
                return View();
            }
        }

        // GET: CountryContinent/Delete/5
        public ActionResult Delete(int id)
        {
            return View();
        }

        // POST: CountryContinent/Delete/5
        [HttpPost]
        public ActionResult Delete(int id, FormCollection collection)
        {
            try
            {
                // TODO: Add delete logic here

                return RedirectToAction("Index");
            }
            catch
            {
                return View();
            }
        }
    }
}

以下是模型：

using System;
using System.Collections;
using System.ComponentModel.DataAnnotations;

namespace TransactionImporter.WebUI.Models
{
    public class CountryContinentModels
    {
        public CountryContinentModels(string country, string continent)
        {
            Country = country;
            Continent = continent;
        }
        public CountryContinentModels() { }
        public int Id { get; private set; }
        [Display(Name = "Country")]
        public string Country { get; private set; }
        [Display(Name = "Continent")]
        public string Continent { get; private set; }

        public IEnumerator GetEnumerator()
        {
            throw new NotImplementedException();
        }
    }
}

Answer 1

当模型绑定发生时，它有助于理解ASP.NET创建模型所采取的步骤，具体来说：

ASP.NET使用默认构造函数创建模型的实例。
如果存在匹配set的HTML输入，则会调用每个属性的name方法。

首先，您需要更改属性以使用公共set方法，如下所示：

public string Continent { get; set; }

这应该可以解决问题，但如果没有，您可以检查HTML中生成的名称，以确保它们与C＃属性的名称相关。

在Form POST

1 个答案: