MVC 4乐观并发异常 [英] MVC 4 Optimistic concurrency exception

问题描述

面对此发布

Having faced this issue (I wanted to allow an edit by using a bootstrap modal window, i'm using MVC4 and entity framework), when I want to save my changes, I have this error message since I'm using the modal window :

Store update, insert, or delete statement affected an unexpected number of rows (0). Entities may have been modified or deleted since entities were loaded. Refresh ObjectStateManager entries.

这是我的操作：

[HttpGet]
        public ActionResult EditPerson(long id)
        {
            var person = db.Persons.Single(p => p.Id_Person == id);

            ViewBag.Id_ProductPackageCategory = new SelectList(db.ProductPackageCategories, "Id_ProductPackageCategory", "Name", person.Id_ProductPackageCategory);

            return PartialView("_EditPerson", person);
        }

        [HttpPost]
        public ActionResult EditPerson(Person person)
        {
            ViewBag.Id_ProductPackageCategory = new SelectList(db.ProductPackageCategories, "Id_ProductPackageCategory", "Name", person.Id_ProductPackageCategory);

            if (ModelState.IsValid)
            {
                ModelStateDictionary errorDictionary = Validator.isValid(person);

                if (errorDictionary.Count > 0)
                {
                    ModelState.Merge(errorDictionary);
                    return View(person);
                }

                db.Persons.Attach(person);
                db.ObjectStateManager.ChangeObjectState(person, EntityState.Modified);
                db.SaveChanges();
                return View("Index");
            }

            return View(person);
        }

我的部分视图：

@model BuSIMaterial.Models.Person

<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
    <h3 id="myModalLabel">Edit</h3>
</div>
<div>

@using (Ajax.BeginForm("EditPerson", "Person", FormMethod.Post,
                    new AjaxOptions
                    {
                        InsertionMode = InsertionMode.Replace,
                        HttpMethod = "POST",
                        UpdateTargetId = "table"
                    }))
{

    @Html.ValidationSummary()
    @Html.AntiForgeryToken()

    <div class="modal-body">
       <div class="editor-label">
            First name :
        </div>
        <div class="editor-field">
            @Html.TextBoxFor(model => model.FirstName, new { maxlength = 50 })
            @Html.ValidationMessageFor(model => model.FirstName)
        </div>
        <div class="editor-label">
            Last name :
        </div>
        <div class="editor-field">
            @Html.TextBoxFor(model => model.LastName, new { maxlength = 50 })
            @Html.ValidationMessageFor(model => model.LastName)
        </div>
        <div class="editor-label">
            National number :
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.NumNat, new { maxlength = 11 })
            @Html.ValidationMessageFor(model => model.NumNat)
        </div>
        <div class="editor-label">
            Start date :
        </div>
        <div class="editor-field">
            @Html.TextBoxFor(model => model.StartDate, new { @class = "datepicker", @Value = Model.StartDate.ToString("yyyy/MM/dd") })
            @Html.ValidationMessageFor(model => model.StartDate)
        </div>
        <div class="editor-label">
            End date :
        </div>
        <div class="editor-field">
            @if (Model.EndDate.HasValue)
            {
                @Html.TextBoxFor(model => model.EndDate, new { @class = "datepicker", @Value = Model.EndDate.Value.ToString("yyyy/MM/dd") })
                @Html.ValidationMessageFor(model => model.EndDate)
            }
            else
            {
                @Html.TextBoxFor(model => model.EndDate, new { @class = "datepicker" })
                @Html.ValidationMessageFor(model => model.EndDate)
            }
        </div>
        <div class="editor-label">
            Distance House - Work (km) :
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.HouseToWorkKilometers)
            @Html.ValidationMessageFor(model => model.HouseToWorkKilometers)
        </div>
        <div class="editor-label">
            Category :
        </div>
        <div class="editor-field">
            @Html.DropDownList("Id_ProductPackageCategory", "Choose one ...")
            @Html.ValidationMessageFor(model => model.Id_ProductPackageCategory) <a href="../ProductPackageCategory/Create">
                Add a new category?</a>
        </div>
        <div class="editor-label">
            Upgrade? :
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Upgrade)
            @Html.ValidationMessageFor(model => model.Upgrade)
        </div>
    </div>
    <div class="modal-footer">
        <button class="btn btn-inverse" type="submit">Save</button>
    </div>
}

关于发生什么的任何想法？

Any idea on what's going on?

推荐答案

首先尝试这个，就在 @ Html.ValidationSummary（）在部分视图中，您具有模态头部，正文和页脚，位置：

Try this first, just above @Html.ValidationSummary() in the partial view where you have the modal head, body and footer, place:

@Html.HiddenFor(model => model.PersonId) // or.Id whatever's in your model

这将在你的视图中创建一个隐藏的字段并设置模型ID，即PK。

This creates a hidden field in your view and sets model ID i.e. PK.

这篇关于MVC 4乐观并发异常的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！