MVC 5 - 如何首先使用 EF 代码更新关系表
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【中文标题】MVC 5 - 如何首先使用 EF 代码更新关系表【英文标题】：MVC 5 - How to update relational table using EF code first 【发布时间】：2019-11-11 23:48:09 【问题描述】：我对 MVC 5 比较陌生，并且在弄清楚如何更新关系表时遇到了问题。我首先使用 EF 代码。我花了很多时间寻找解决方案，但我找不到任何与我的代码相关的东西，这就是为什么我除了在这里问之外别无选择，所以如果这个问题已经得到解答，我先道歉。
我将关系表包含在我的 Razor 视图中，效果非常好。但是当我想更新表格时，即使我当前的代码没有错误，它也不会更新。 我还尝试添加一个额外的 Bind[(Include = "Id,FirstName,LastName")]，但这使用了 Booking FirstName 和 LastName。 我不确定我的方法是否是“正确的”方法。我的逻辑告诉我，我需要从视图中获取数据并在控制器中检索它们，但我不知道如果我不能使用 Bind 或 db.Entry(item).State = EntityState.Modified?
Booking.cs
namespace Ventures.Innovation.InteractiveModel.Context
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Data.Entity.Spatial;
public partial class Bookings
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
public Bookings()
AttendingPeople = new HashSet<AttendingPeople>();
public int Id get; set;
[Required]
[StringLength(128)]
public string AspNetUserFk get; set;
[Required]
public DateTime Date get; set;
[Required]
[StringLength(100)]
public string FirstName get; set;
[Required]
[StringLength(50)]
public string LastName get; set;
public virtual AspNetUsers AspNetUsers get; set;
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
public virtual ICollection<AttendingPeople> AttendingPeople get; set;
AttendingPeople.cs
namespace Ventures.Innovation.InteractiveModel.Context
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Data.Entity.Spatial;
public partial class AttendingPeople
public int Id get; set;
public int BookingId get; set;
[Required]
[StringLength(100)]
public string FirstName get; set;
[Required]
[StringLength(50)]
public string LastName get; set;
public virtual Bookings Bookings get; set;
控制器
// GET: AdminHome/Edit/5
public ActionResult Edit(int? id)
if (id == null)
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
Bookings bookings = db.Bookings.Find(id);
if (bookings == null)
return HttpNotFound();
ViewBag.AspNetUserFk = new SelectList(db.AspNetUsers, "Id", "Email", bookings.AspNetUserFk);
var attendingPeople = db.AttendingPeople.Where(a => a.BookingId == id).ToList();
bookings.AttendingPeople = attendingPeople;
return View(bookings);
// POST: AdminHome/Edit/5
// To protect from overposting attacks, please enable the specific properties you want to bind to, for
// more details see https://go.microsoft.com/fwlink/?LinkId=317598.
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Edit([Bind(Include = "Id,AspNetUserFk,Date,FirstName,LastName")] Bookings bookings)
if (ModelState.IsValid)
db.Entry(bookings).State = EntityState.Modified;
db.SaveChanges();
var editedAttendingPeople = db.AttendingPeople.Where(a => a.BookingId == bookings.Id).ToList();
foreach (var item in editedAttendingPeople)
db.Entry(item).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
ViewBag.AspNetUserFk = new SelectList(db.AspNetUsers, "Id", "Email", bookings.AspNetUserFk);
return View(bookings);
查看
@model Ventures.Innovation.InteractiveModel.Context.Bookings
@
ViewBag.Title = "Edit booking";
<h2>Edit booking</h2>
<hr />
@using (html.BeginForm())
@Html.AntiForgeryToken()
<div class="form-horizontal">
@Html.ValidationSummary(true, "", new @class = "text-danger" )
@Html.HiddenFor(model => model.Id)
</div>
<div class="form-group">
@Html.LabelFor(model => model.AspNetUserFk, htmlAttributes: new @class = "control-label col-md-2" )
<div class="col-md-10">
@Html.DropDownList("AspNetUserFk", null, htmlAttributes: new @class = "form-control" )
@Html.ValidationMessageFor(model => model.AspNetUserFk, "", new @class = "text-danger" )
</div>
</div>
<div class="form-group">
@Html.LabelFor(model => model.Date, htmlAttributes: new @class = "control-label col-md-2" )
<div class="col-md-10">
@Html.EditorFor(model => model.Date, new htmlAttributes = new @class = "form-control" )
@Html.ValidationMessageFor(model => model.Date, "", new @class = "text-danger" )
</div>
</div>
<div class="form-group">
@Html.LabelFor(model => model.FirstName, htmlAttributes: new @class = "control-label col-md-2" )
<div class="col-md-10">
@Html.EditorFor(model => model.FirstName, new htmlAttributes = new @class = "form-control" )
@Html.ValidationMessageFor(model => model.FirstName, "", new @class = "text-danger" )
</div>
</div>
<div class="form-group">
@Html.LabelFor(model => model.LastName, htmlAttributes: new @class = "control-label col-md-2" )
<div class="col-md-10">
@Html.EditorFor(model => model.LastName, new htmlAttributes = new @class = "form-control" )
@Html.ValidationMessageFor(model => model.LastName, "", new @class = "text-danger" )
</div>
</div>
@if (Model.AttendingPeople.Count > 0)
@Html.Label("Attending people")
foreach (var attendingPeople in Model.AttendingPeople)
<div class="form-group">
<div class="col-md-10">
@Html.LabelFor(modelItem => attendingPeople.FirstName, htmlAttributes: new @class = "control-label col-md-5", @style = "padding-left: 0;" )
@Html.LabelFor(modelItem => attendingPeople.LastName, htmlAttributes: new @class = "control-label col-md-5", @style = "padding-left: 0;" )
</div>
<div class="col-md-10">
@Html.EditorFor(modelItem => attendingPeople.FirstName, new htmlAttributes = new @class = "form-control col-md-5", @style = "display: initial;" )
@Html.EditorFor(modelItem => attendingPeople.LastName, new htmlAttributes = new @class = "form-control col-md-5", @style = "display: initial;" )
</div>
</div>
<div class="form-group">
<div class="col-md-offset-2 col-md-10">
<input type="submit" value="Save changes" class="btn btn-primary" />
</div>
</div>
</div>
@section Scripts
@Scripts.Render("~/bundles/jqueryval")
我想将更新后的数据保存到数据库中的 AttendingPeople 表中，但没有任何反应。
【问题讨论】：
好的，我现在知道代码：db.Entry(item).State = EntityState.Modified;实际上没有做任何事情，因为它没有更新。我不明白的是，即使我成功地将AttendingPeople 添加到Bookings，并且能够在视图中执行循环，我也没有从视图中得到任何东西到控制器，这意味着bookings.AttendingPeople。计数为 0。我想我需要检索 AttendingPeople 数据并将它们发送到控制器，但是如何？ 到目前为止花了 2 天时间。我注意到 FormCollection 只有 1 个参加人[0].姓氏。但仍然没有更接近解决方案。 您的表单是否按预期绑定回控制器操作？你的问题很窄，但你的代码示例很广泛。我注意到的一件事是在您的控制器中更重要的一点是有一条评论“// POST：AdminHome/Edit/5”，当您点击“保存”时，您似乎是从“预订”视图发布的（提交) 按钮，您是否调试过使用开发人员工具进行的 xhr 请求？它是否会使用您期望的表单数据进入正确的控制器和操作？ 是的，它从脚手架编辑页面转到正确的控制器和操作，即具有 Booking 作为参数的 Edit 方法。但是当我按下保存时，我不确定如何将 AttendingPeople 更改绑定到 Booking。在顶部的 Edit 方法中，我将 AttendingPeople 添加到 Booking，在我的视图 (Edit.cshtml) 中，我可以从 Model 中获取值。我尝试在 Edit 方法的参数中添加“ICollection AttendPeople”甚至“string[] AttendPeople”，但它们始终为空。 您的 AttendingPeople 在视图中的填充是否正确？您还检查过哪些 html 被渲染为 html 吗？您的参加者是否被添加为数组对象，例如编辑器字段的 id 是 AttendingPeople[0]、AttendingPeople[1] 等？这就是我要参考的内容-***.com/questions/19964553/… 上的投票答案 --- 请注意，您不需要在答案中将解决方案实现为编辑器/显示模板。还有其他方法。 【参考方案1】：感谢 JARRRRG 在这里帮助我。 :)
为了解决这个问题，我需要确保我的命名完全相同。显然这就是它从视图中查找/绑定到控制器的方式。我还需要确保我使用了 for 循环，以便集合可以区分对象。
这是我的更新视图：
@if (Model.AttendingPeople.Count > 0)
@Html.Label("Attending people")
var attendingPeople = Model.AttendingPeople.ToArray();
foreach (int i = 0; i < attendingPeople.Length; i++)
@Html.HiddenFor(modelItem => attendingPeople[i].Id)
<div class="form-group">
<div class="col-md-10">
@Html.LabelFor(modelItem => attendingPeople[i].FirstName, htmlAttributes: new @class = "control-label col-md-5", @style = "padding-left: 0;" )
@Html.LabelFor(modelItem => attendingPeople[i].LastName, htmlAttributes: new @class = "control-label col-md-5", @style = "padding-left: 0;" )
</div>
<div class="col-md-10">
@Html.EditorFor(modelItem => attendingPeople[i].FirstName, new htmlAttributes = new @class = "form-control col-md-5", @style = "display: initial;" )
@Html.EditorFor(modelItem => attendingPeople[i].LastName, new htmlAttributes = new @class = "form-control col-md-5", @style = "display: initial;" )
</div>
</div>
这是我的新编辑：
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Edit([Bind(Include = "Id,AspNetUserFk,Date,FirstName,LastName")] Bookings bookings, ICollection<AttendingPeople> attendingPeople)
if (ModelState.IsValid)
db.Entry(bookings).State = EntityState.Modified;
db.SaveChanges();
foreach (var item in attendingPeople)
item.BookingId = bookings.Id;
db.Entry(item).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
ViewBag.AspNetUserFk = new SelectList(db.AspNetUsers, "Id", "Email", bookings.AspNetUserFk);
bookings = db.Bookings.Include(at => at.AttendingPeople).SingleOrDefault(b => b.Id == bookings.Id)
return View(bookings);
【讨论】：
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