我收到错误处理请求时发生未处理的异常

Question

我刚开始学习 ASP.net Core，我遇到了这个错误：

我一直在网上搜索解决方案，但没有得到任何结果。谁能帮我？这是我的代码：

Details.cshtml

@model SixthApp.Models.Customer

@{
    ViewData["Title"] = "Details";
}

<h1>Details</h1>

<div>
    <h4>Customer</h4>
    <p>@ViewData["data"]</p>

    <hr />
    <dl class="row">
        <dt class = "col-sm-2">
            @Html.DisplayNameFor(model => model.CustomerId)
        </dt>
        <dd class = "col-sm-10">
            @Html.DisplayFor(model => model.CustomerId)
        </dd>
        <dt class = "col-sm-2">
            @Html.DisplayNameFor(model => model.Name)
        </dt>
        <dd class = "col-sm-10">
            @Html.DisplayFor(model => model.Name)
        </dd>
        <dt class = "col-sm-2">
            @Html.DisplayNameFor(model => model.Address)
        </dt>
        <dd class = "col-sm-10">
            @Html.DisplayFor(model => model.Address)
        </dd>
        <dt class = "col-sm-2">
            @Html.DisplayNameFor(model => model.MobileNo)
        </dt>
        <dd class = "col-sm-10">
            @Html.DisplayFor(model => model.MobileNo)
        </dd>
    </dl>
</div>
<div>
    @Html.ActionLink("Edit", "Edit", new { /* id = Model.PrimaryKey */ }) |
    <a asp-action="Index">Back to List</a>
</div>

这是CustomerController.cs

中的详细方法

        public IActionResult Details(int? Id)
        {
            var DataCustomer = _conn.tabel_customer.Where(c => c.CustomerId == Id).ToList();

            return View(DataCustomer);
        }

Answer 1

    public IActionResult Details(int? Id)
    {
        var DataCustomer = _conn.tabel_customer.Where(c => c.CustomerId == Id).ToList();

        return View(DataCustomer);
    }

您的视图需要的类型是 model，您在操作中 return 到视图的类型是 list

试试下面的代码：

    public async Task<IActionResult> Details(int? Id)
    {
        var DataCustomer =  await _conn.tabel_customer.FirstOrDefaultAsync(c => c.CustomerId == Id);

        return View(DataCustomer);
    }

Answer 2

您正在 return 查看对象列表，而视图需要一个对象。
您应该将您的控制器更改为这样的东西，更改为 return 单个对象：

public IActionResult Details(int? Id)
{
    var DataCustomer = _conn.tabel_customer.Where(c => c.CustomerId == Id).FirstOrDefault();

    return View(DataCustomer);
}

或将模型更改为 @model IEnumerable<SixthApp.Models.Customer> 并在视图中循环遍历它以显示您从控制器获得的所有对象....

我收到错误处理请求时发生未处理的异常

I got Error An unhandled exception occurred while processing the request

asp.net

razor

asp.net-mvc-4

asp.net-core

blazor