Question

我遇到了实现ViewModel类的问题，该类充当了由L2SQL生成的名为“User”的Model类的包装类。简而言之，当我必须验证L2SQL模型时，我有两个实例。一个是用户首次注册时，另一个是用户登录时仅编辑部分帐户数据。

最初的“问题”是在尝试编辑＆amp;仅从一个仅显示少数（例如FirstName，LastName，Email）的View中验证原始L2SQL模型的一些帐户详细信息，在运行验证时，将丢失的（例如密码）。密码设置将有自己的视图。

我在StackOverflow上建议添加一个包装ViewModel类是最好的解决方案。所以我做了，实现如下：

ViewModel代码：

[Bind]
public class AccountEdit 
{ 
    public User UserAccount { get; set; } 

    [Required(ErrorMessage = "First name required"), StringLength(20, MinimumLength = 3, ErrorMessage = "Must be between 3 and 20 characters")]   
    public string FirstName  { get { return UserAccount.FirstName; } set { UserAccount.FirstName = value; } }

    [Required(ErrorMessage = "Last name required"), StringLength(20, MinimumLength = 3, ErrorMessage = "Must be between 3 and 20 characters")]
    public string LastName { get { return UserAccount.LastName; } set { UserAccount.LastName = value; } }

    [Required(ErrorMessage = "Email address required"), RegularExpression("^[a-z0-9_\\+-]+(\\.[a-z0-9_\\+-]+)*@[a-z0-9-]+(\\.[a-z0-9-]+)*\\.([a-z]{2,4})$", ErrorMessage = "Must be a valid email address")]
    public string Email { get { return UserAccount.Email; } set { UserAccount.Email = value; } }
}

控制器代码：

//
// GET /User/Account
public ActionResult Account()
{
    string cookieUser = User.Identity.Name;
    User user = userRepository.GetUserByEmail(cookieUser);
    return View(user);
}

// POST /User/Account
[HttpPost]
public ActionResult Account(AccountEdit model)
{                
    if (ModelState.IsValid)
    {
        model.LastUpdated = DateTime.Now; 
        userRepository.Save();
    }
    return View(model);
}

Veiw代码：

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/User.Master" Inherits="System.Web.Mvc.ViewPage<Digitalent.Models.User>" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
    Account settings
</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

<% using (Html.BeginForm()) {%>

    <%= Html.ValidationSummary("Oops! Please correct the errors and try again!") %>

        <p>
            <label for="FirstName">First name:</label>
            <%: Html.TextBoxFor(model => model.FirstName, new { @class = "textfield" })%> 
            <%: Html.ValidationMessageFor(model => model.FirstName) %>
        </p>

        <p>
            <label for="LastName">Last name:</label>
            <%: Html.TextBoxFor(model => model.LastName, new { @class = "textfield" })%> 
            <%: Html.ValidationMessageFor(model => model.LastName) %>
        </p>

        <p>
            <label for="Email">Email address:</label>
            <%: Html.TextBoxFor(model => model.Email, new { @class = "textfield" })%> 
            <%: Html.ValidationMessageFor(model => model.Email) %>
        </p>

        <p>
            Email newsletter: <%= Html.CheckBoxFor(model => model.EmailNewsletter) %>
            <label for="EmailNewsletter">Keep me posted with latest Digitalent happenings.</label>
        </p>


        <p>
            <input type="submit" value="Save changes" class="button" />
        </p>

        <p><a href="/talent/password">Change your password settings</a></p>

<% } %>

但是现在当我试图运行应用程序时，我在运行验证时遇到错误：

'对象引用未设置为对象的实例。'

在我的ViewModel中的下面一行：

'public string FirstName {get {return UserAccount.FirstName; } set {UserAccount.FirstName = value; '}

我在哪里出错或者其他人可以告诉我更好的推荐方法，因为我是新手。求救！

Answer 1

更改您的观点：

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/User.Master" 
    Inherits="System.Web.Mvc.ViewPage<Digitalent.Models.User>" %>

为：

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/User.Master" 
    Inherits="System.Web.Mvc.ViewPage<Digitalent.Models.AccountEdit>" %>

使用L2SQL生成的模型类的ViewModel验证对象问题

1 个答案: