无法访问模型类中定义的对象

Question

我正在尝试列出数据库中显示的数据，我创建了一个 ViewingGoals 类并在 ViewingGoalsBusinessLayer 类中实现其业务逻辑，代码如下

查看目标.cs：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace BusinessLayer
{
  public class ViewingGoals
    {
        public string Goal { get; set; }
    }
}

查看GoalsBusinessLayer.cs：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using BusinessLayer;

namespace BusinessLayer
{
    public class ViewingGoalsBusinessLayer
    {
        public void ViewData(ViewingGoals viewgoal)
        {
            try
            {
                string Connectionstring = ConfigurationManager.ConnectionStrings["Connectionstring"].ConnectionString;
                List<ViewingGoals> viewgoals = new List<ViewingGoals>();
                using (SqlConnection con = new SqlConnection(Connectionstring))
                {
                    SqlCommand cmd = new SqlCommand("ViewGoal", con);
                    cmd.CommandType = CommandType.StoredProcedure;
                    con.Open();
                    SqlDataReader rdr = cmd.ExecuteReader();
                    while (rdr.Read())
                    {
                        //ViewingGoals viewgoal = new ViewingGoals();
                        viewgoal.Goal = rdr["Goal"].ToString();
                        viewgoals.Add(viewgoal);
                    }
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
    }
}

我的控制器代码是：

查看目标控制器.cs：

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

namespace AppraisalManagementSystemFinal.Controllers
{
    public class ViewingGoalsController : Controller
    {
        //
        // GET: /ViewingGoals/

        public ActionResult ViewingGoals()
        {
            ViewingGoalsBusinessLayer viewinggoalsbusinessLayer = new ViewingGoalsBusinessLayer();
            List<ViewingGoals> viewgoals = viewinggoalsbusinessLayer.viewgoal.ToList();

            return View(viewgoals);
        }

    }
}

在那个控制器中，我试图从 ViewingGoalBusinessLayer 访问对象 列出 viewgoals = 查看目标businessLayer.viewgoal.ToList();我收到错误，因为不包含 viewgoal 的定义。

请帮助我克服它。

Answer 1

当您使用viewinggoalsbusinessLayer.viewgoal 时，您正在尝试从您的viewinggoalsbusinessLayer 对象访问viewgoal 属性。
问题是您还没有在该对象中定义这样的属性！
这是您的代码的更新部分

public class ViewingGoalsBusinessLayer
    {
        public List<ViewingGoals> ViewGoals;
        public void ViewData(ViewingGoals viewgoal)
        {
            try
            {
                string Connectionstring = ConfigurationManager.ConnectionStrings["Connectionstring"].ConnectionString;
                Viewgoals = new List<ViewingGoals>();
                // Rest of code is unchanged ...
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
    }

下一个问题是您需要初始化该列表，我不确定您的 ViewData 函数在做什么...