如何在下一页的表格中列出信息
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【中文标题】如何在下一页的表格中列出信息【英文标题】：how do i list information from a form on the next page 【发布时间】：2021-12-08 16:23:07 【问题描述】：我正在尝试创建一个表单，用户可以在其中输入他们的信息。他们单击提交，然后在下一页上列出了他们的信息。我创建了两页。创建模板的一个视图页面 (Book.cshtml)。在另一个视图页面 (Review.cshtml) 上，模板是列表。他们的两个模型类都取自 Form.cs 模型。我的问题是，当我单击提交时，它给了我这个错误，“System.NullReferenceException：'对象引用未设置为对象的实例。'。”我猜这是因为没有信息存储在 Book.cshtml 中的 Form.cs 模型中。如何存储用户在 Book 页面上输入的信息，并在 Review 页面上显示。我尝试使用 [HttpGet] 和 [HttpPost]，但没有任何反应。我正在使用 Visual Studio asp.net core MVC 3.1
家庭控制器
using Hotel_Lodge.Models;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
namespace Hotel_Lodge.Controllers
public class HomeController : Controller
private readonly ILogger<HomeController> _logger;
public HomeController(ILogger<HomeController> logger)
_logger = logger;
public IActionResult Index()
return View();
[HttpGet]
public IActionResult Book()
return View();
[HttpPost]
public IActionResult Book(Form form)
return View();
public IActionResult Review()
return View();
public IActionResult Privacy()
return View();
[ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
public IActionResult Error()
return View(new ErrorViewModel RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier );
Form.cs 模型
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace Hotel_Lodge.Models
public class Form
public string Name get; set;
public string Arrival get; set;
public string Departure get; set;
public string RoomType get; set;
public string Misc get; set;
Book.cshtml（视图）
@model Hotel_Lodge.Models.Form
@
ViewData["Title"] = "Book";
<h1>Book</h1>
<h4>Form</h4>
<hr />
<div class="row">
<div class="col-md-4">
<form asp-action="Book">
<div asp-validation-summary="ModelOnly" class="text-danger"></div>
<div class="form-group">
<label asp-for="Name" class="control-label"></label>
<input asp-for="Name" class="form-control" />
<span asp-validation-for="Name" class="text-danger"></span>
</div>
<div class="form-group">
<label asp-for="Arrival" class="control-label"></label>
<input asp-for="Arrival" class="form-control" />
<span asp-validation-for="Arrival" class="text-danger"></span>
</div>
<div class="form-group">
<label asp-for="Departure" class="control-label"></label>
<input asp-for="Departure" class="form-control" />
<span asp-validation-for="Departure" class="text-danger"></span>
</div>
<div class="form-group">
<label asp-for="RoomType" class="control-label"></label>
<input asp-for="RoomType" class="form-control" />
<span asp-validation-for="RoomType" class="text-danger"></span>
</div>
<div class="form-group">
<label asp-for="Misc" class="control-label"></label>
<input asp-for="Misc" class="form-control" />
<span asp-validation-for="Misc" class="text-danger"></span>
</div>
<div>
<a type="submit" class="btn btn-dark" href="https://localhost:44348/Home/Review">Next</a>
</div>
</form>
</div>
</div>
<div>
<a asp-action="Index">Back to List</a>
</div>
@section Scripts
@await Html.RenderPartialAsync("_ValidationScriptsPartial");
Review.cshtml（查看）
@model IEnumerable<Hotel_Lodge.Models.Form>
@
ViewData["Title"] = "Review";
<h1>Review</h1>
<p>
<a asp-action="Create">Create New</a>
</p>
<table class="table">
<thead>
<tr>
<th>
@Html.DisplayNameFor(model => model.Name)
</th>
<th>
@Html.DisplayNameFor(model => model.Arrival)
</th>
<th>
@Html.DisplayNameFor(model => model.Departure)
</th>
<th>
@Html.DisplayNameFor(model => model.RoomType)
</th>
<th>
@Html.DisplayNameFor(model => model.Misc)
</th>
<th></th>
</tr>
</thead>
<tbody>
@foreach (var item in Model)
<tr>
<td>
@Html.DisplayFor(modelItem => item.Name)
</td>
<td>
@Html.DisplayFor(modelItem => item.Arrival)
</td>
<td>
@Html.DisplayFor(modelItem => item.Departure)
</td>
<td>
@Html.DisplayFor(modelItem => item.RoomType)
</td>
<td>
@Html.DisplayFor(modelItem => item.Misc)
</td>
<td>
@Html.ActionLink("Edit", "Edit", new /* id=item.PrimaryKey */ ) |
@Html.ActionLink("Details", "Details", new /* id=item.PrimaryKey */ ) |
@Html.ActionLink("Delete", "Delete", new /* id=item.PrimaryKey */ )
</td>
</tr>
</tbody>
</table>
【问题讨论】：
【参考方案1】：您没有在您的操作中创建任何模型，这就是您出现空引用错误的原因。例如 Review 应该是这样的
public class HomeController : Controller
private readonly ILogger<HomeController> _logger;
private readonly DbContext _context
public HomeController(
ILogger<HomeController> logger,
DbContext context
)
_logger = logger;
_context=context
public IActionResult Review()
var model= _context.Set<FormModel>().ToList();
return View(model);
【讨论】：
【参考方案2】：我建议您使用提交按钮而不是href（请参阅ASP.NET MVC Form Submit with Link instead of Button）。
替换Book.cshtml中的以下行
<a type="submit" class="btn btn-dark" href="https://localhost:44348/Home/Review">Next</a>
通过
<button type="submit" class="btn btn-primary">Next</button>
所以，点击Next会将Form对象传递给Book(Form form)。
并将Book(Form form) 方法更新为：
[HttpPost]
public IActionResult Book(Form form)
if (!ModelState.IsValid)
return RedirectToAction("Index", form);
// You should add the current a new record to a repository here
// and pass an updated list to the `Review`.
// Currently only a new `form` record is passed to the `Review` for demo purpose.
return View("Review", new List<Form> form );
【讨论】：
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