Question

很抱歉，如果措辞不好，但我很困惑，已经很晚了，但是我会尽力解释。因此，我尝试不使用实体框架将数据库中的所有订单显示到表中。问题是，当我转到orders / getAllOrders时，我得到一个大错误，说“视图”，然后是一堆

 <tr><td>2</td><td>Javier</td><td>1</td><td>Groovestring</td><td>3.950000</td></tr>etc..

其中包含我的数据，但我不知道如何正确显示它。我知道我的查询工作正常，并且可以很好地检索我的数据，但是在显示它时我很困惑

这是我目前为控制器提供的。

namespace Website.Controllers
{
public class OrderController : Controller
{

    private static bool CanConnectToDb()
    {
        var cnn = new SqlConnection(ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString);
        try
        {
            cnn.Open();
            return true;
        }
        catch (Exception exception)
        {
            return false;
        }
        finally
        {
            if (cnn.State != ConnectionState.Closed)
                cnn.Close();
        }
    }


    public ActionResult getAllOrders()
    {
        // Connect to Database
        var cnn = new SqlConnection(ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString);
        cnn.Open();
        // Create Command
        SqlCommand cmd = new SqlCommand(
            @"SELECT CustomerOrderId, FirstName ,ProductId, [Name], Price
                FROM OrderProduct AS o
                INNER JOIN CustomerOrder co ON co.id = o.CustomerOrderId
                INNER JOIN Product p ON p.Id = o.ProductId
                INNER JOIN Customer c ON c.Id = co.CustomerId
                ORDER BY ProductId"
            );

        cmd.Connection = cnn;
        string store = "";
        // Read from Database
        SqlDataReader reader = cmd.ExecuteReader();

        var orders = new OrderIndexViewModel();
        while (reader.Read())
        {
            orders.CustomerOrderId = reader.GetInt32(0);
            orders.FirstName = reader.GetString(1);
            orders.ProductId = reader.GetInt32(2);
            orders.Name = reader.GetString(3);
            orders.Price = reader.GetDecimal(4);
            store += "<tr><td>" + orders.CustomerOrderId + "</td><td>" + orders.FirstName + "</td><td>" + orders.ProductId + "</td><td>" + orders.Name + "</td><td>" + orders.Price + "</td></tr>";
        }
        cnn.Close();
        return View(store);
    }
  }
}

编辑：当我将返回值更改为

rerturn View(orders);

我收到此错误

The model item passed into the dictionary is of type 'Website.Models.OrderIndexViewModel', but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable`1[Website.Models.OrderIndexViewModel]'.

这是我的模特

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace Website.Models
{
    public class OrderIndexViewModel
    {
        public int CustomerOrderId { get; set; }
        public string FirstName { get; set; }
        public int ProductId { get; set; }
        public string Name { get; set; }
        public decimal Price { get; set; }
    }
}

最后这就是我的观点

@model IEnumerable<Website.Models.OrderIndexViewModel>  
@{
    ViewBag.Title = "getAllOrders";
    Layout = "~/Views/Shared/_Layout.cshtml";
}

<h2>getAllOrders</h2>

<p>
    @Html.ActionLink("Create New", "Create")
</p>
<table class="table">
    <tr>
        <th>
            Customer Oder Id
        </th>
        <th>
            First Name
        </th>
        <th>
            ProductId
        </th>
        <th>
            Name
        </th>
        <th>
            Price
        </th>
    </tr>
    @foreach (var item in Model)
    {
        <tr>
            <td>
                @Html.DisplayFor(modelItem => item.CustomerOrderId)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.FirstName)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.ProductId)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.Name)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.Price)
            </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>
    }
</table>

任何帮助都会得到感激

Answer 1

您已将字符串发送到模型，但必须将集合发送到模型，然后在表中显示

Answer 2

您的视图期望使用IEnumerable<Website.Models.OrderIndexViewModel>作为模型，但是您要向其传递Website.Models.OrderIndexViewModel的单个实例。

这可能是代码中的另一个错误，因为这只会渲染select语句中的最后一项。因此，您需要这样的东西，它将为每个结果渲染一行：

var orders = new List<OrderIndexViewModel>();
    while (reader.Read())
    {
        var order = new OrderIndexViewModel();
        order.CustomerOrderId = reader.GetInt32(0);
        order.FirstName = reader.GetString(1);
        order.ProductId = reader.GetInt32(2);
        order.Name = reader.GetString(3);
        order.Price = reader.GetDecimal(4);
        orders.Add(order);
    }
    cnn.Close();
    return View(orders);

ASP.NET Razor-如何显示数据库中多个表中的数据

2 个答案: