Question

我是C＃MVC ASP.NET的新手。我无法弄清楚为什么我会得到这个例外。有人可以帮我这个吗？

尝试登录后出现异常：

类型＆＃39; System.NullReferenceException＆＃39;的例外情况发生在App_Web_stjzfqjl.dll中但未在用户代码中处理

控制器代码：

public class LoginController : DatabaseController
{
    // GET: Login
    public ActionResult Login(string email, string wachtwoord)
    {
        int verificatie = 0;

        try
        {

            Session.RemoveAll();

            connection.Open();

            string selectQuery = "SELECT wachtwoord, is_beheerder, is_manager, gebruiker_id, voornaam, achternaam from gebruiker where email = @emailadres";
            MySqlCommand cmd = new MySqlCommand(selectQuery, connection);
            MySqlParameter emailParam = new MySqlParameter("@emailadres", MySqlDbType.VarChar);
            cmd.Parameters.Add(emailParam);
            emailParam.Value = email;

            MySqlDataReader dataReader = cmd.ExecuteReader();

            while (dataReader.Read())
            {

                   var gebruiker = new Gebruiker
                 { voornaam = dataReader.GetString("voornaam"),
                     achternaam = dataReader.GetString("achternaam"),
                     is_beheerder = dataReader.GetInt32("is_beheerder"),
                     wachtwoord = dataReader.GetString("wachtwoord"),
                     is_manager = dataReader.GetInt32("is_manager")
                   };


                if (gebruiker.wachtwoord == wachtwoord)
                {
                    verificatie = 1;

                }
                if(gebruiker.is_beheerder == 1)
                {

                    Session["Beheerder"] = gebruiker;


                }
                else
                {

                    Session["Gebruiker"] = gebruiker;


                }

            }
        }
        catch (Exception e)
        {
            ViewBag.error = email + e;
            return View();
        }
        finally
        {
            connection.Close();
        }

        if (verificatie == 1)
        {
            ViewBag.error = "Verificatie is GOED";
            Response.Redirect("~/Home/Index");
        }
        else
        {
            ViewBag.error= email + " " + wachtwoord;
        }
    return View(gebruiker);
}

在布局视图中：

@model DeGeenery.Models.Gebruiker

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>@ViewBag.Title - The Greenery</title>
<link rel="shortcut icon" href="~/Content/images/favicon.png">
<link href="~/Content/Sitev2.css" rel="stylesheet" type="text/css" />
<script src="~/Scripts/modernizr-2.6.2.js"></script>
<script src="~/Scripts/jquery-1.10.2.min.js"></script>
<script src="~/Scripts/bootstrap.min.js"></script>
</head>
<body>
<div class="wrapper">
    <div class="header">
    <div id="logo"><a href="index.html"><img src="~/Content/logo.png" />          </a></div>
        <div id="basket"><a href=@Url.Action("Index", "Winkelwagen")><img   src="~/Content/basket.png" /></a></div>
    </div>
    <div class="navbar">
        <ul>
            <li><a href=@Url.Action("Index", "Home")>Home</a></li>
            <li><a href=@Url.Action("Index", "Webshop")>Webshop</a></li>
            <li><a href=@Url.Action("Index", "OverOns")>Over ons</a></li>
            <li><a href=@Url.Action("Index", "Contact")>Contact</a></li>
            @if (Session["Gebruiker"] == null && Session["Beheerder"] == null)
            {
                <li style="float:right;"><a href=@Url.Action("Login","Login")>Login</a></li>
            }
            @if (Session["Beheerder"] != null)
            {
                <li style="float:right;"><a href=@Url.Action("Loguit", "Login")>Log uit</a></li>
                <li style="float:right;"><a href=@Url.Action("Index", "Beheer")>Beheer</a></li>
                <li style="float:right; color: white; margin-right: 10px;"><h4><a href="">Welkom, @Model.voornaam </a></h4></li>
            }
            else if (Session["Gebruiker"] != null)
            {
                <li style="float:right;"><a href=@Url.Action("Loguit","Login")>Log uit</a></li>
                <li style="float:right;">Welkom, @ViewBag.voornaam          ViewBag.achternaam</li>
            }
        </ul>
    </div>
    <div class="body">
        @RenderBody()
    </div>
    <div class="footer">
        Copyright De Greenery &copy; 2016
    </div>
</div>

无法在de view模式MVC中获取模型

0 个答案: