c# - ASP.NET MVC2 - 使用 LINQ 生成的类(验证问题)

Question

关于 ASP.NET MV2，我几乎没有什么不清楚的地方。在数据库中，我有包含多个字段的表 Contacts，还有一个类型为 xml 的附加字段 XmlFields。在该字段中存储了额外的描述字段。
有4个类:

1. Contact 类，对应于Contact表，创建LINQ类时默认定义
2. ContactListView 继承的类Contact 类，有一些额外的属性
3. ContactXmlView 包含的类来自 XmlFields 字段的字段
4. ContactDetailsView 类合并 ContactListView 和ContactXmlView 到一个类中这个是用来显示数据的查看页面

ContactListView 类重新定义了 Contact 类的一些属性(以便我可以添加用于验证的 [Required] 过滤器)-但我收到警告信息:

'ObjectTest.Models.Contacts.ContactListView.FirstName' hides inherited member 'SA.Model.Contact.FirstName'. Use the new keyword if hiding was intended.

ContactDetailsView 类也在创建新联系人并将其添加到数据库时用在表单中。

我不确定这是否正确，警告消息让我有点困惑。对此有何建议？

谢谢，
艾尔

编辑

根据 Jakob's instructions我从头开始尝试:

[MetadataType(typeof(Person_Validation))]
    public partial class Person
    {
    }

    public class Person_Validation 
    {
        [Required]
        string FirstName { get; set; }

        [Required]
        string LastName { get; set; }

        [Required]
        int Age { get; set; }
    }

在 Controller 中我有这个:

[HttpPost]
        public ActionResult Create(Person person, FormCollection collection)
        {
            if (ModelState.IsValid)
            {
                try
                {
                    personRepository.Add(person);
                    personRepository.Save();
                }
                catch
                {
                    return View(person);
                }
            }

            return RedirectToAction("Index");            
        }

查看:

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

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

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

    <h2>Create</h2>

    <% using (Html.BeginForm()) {%>
        <%= Html.ValidationSummary(true) %>

        <fieldset>
            <legend>Fields</legend>           

            <div class="editor-label">
                <%= Html.LabelFor(model => model.FirstName) %>
            </div>
            <div class="editor-field">
                <%= Html.TextBoxFor(model => model.FirstName) %>
                <%= Html.ValidationMessageFor(model => model.FirstName) %>
            </div>

            <div class="editor-label">
                <%= Html.LabelFor(model => model.LastName) %>
            </div>
            <div class="editor-field">
                <%= Html.TextBoxFor(model => model.LastName) %>
                <%= Html.ValidationMessageFor(model => model.LastName) %>
            </div>

            <div class="editor-label">
                <%= Html.LabelFor(model => model.Age) %>
            </div>
            <div class="editor-field">
                <%= Html.TextBoxFor(model => model.Age) %>
                <%= Html.ValidationMessageFor(model => model.Age) %>
            </div>

            <p>
                <input type="submit" value="Create" />
            </p>
        </fieldset>

    <% } %>

    <div>
        <%= Html.ActionLink("Back to List", "Index") %>
    </div>

</asp:Content>

当发布没有值的新人时，没有任何反应(页面只是重新加载)。使用某些值发布时，人员会添加到数据库中。我不知道我做错了什么。

编辑 2

我认为问题出在已经生成部分类 Person 的 LINQ 中。当我定义新的部分类 Person 并单击它并“转到定义”时，我收到以下警告:

C:\Documents and Settings\Korisnik\My Documents\Visual Studio 2008\Projects\Validate\Validate\Models\DataClasses1.designer.cs - (78, 23) : Validate.Models.Person

C:\Documents and Settings\Korisnik\My Documents\Visual Studio 2008\Projects\Validate\Validate\Models\PersonRepository.cs - (11, 26) : Validate.Models.Person

这是 LINQ 生成的类的一部分:

[Table(Name="dbo.Persons")]
 public partial class Person : INotifyPropertyChanging, INotifyPropertyChanged
 {

  private static PropertyChangingEventArgs emptyChangingEventArgs = new PropertyChangingEventArgs(String.Empty);

  private int _PersonID;

  private string _FirstName;

  private string _LastName;

  private string _Age;

                ...

我很确定这是原因，但我不知道如何解决这个问题。有什么想法吗？

编辑 3
好的，让我们从头开始……这是文件夹结构:

http://img535.imageshack.us/img535/3187/70090809.gif http://img227.imageshack.us/img227/6643/15910591.gif

Dataclasses1.designer.cs:

#pragma warning disable 1591
//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//     Runtime Version:2.0.50727.3603
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace Validate.Models
{
 using System.Data.Linq;
 using System.Data.Linq.Mapping;
 using System.Data;
 using System.Collections.Generic;
 using System.Reflection;
 using System.Linq;
 using System.Linq.Expressions;
 using System.ComponentModel;
 using System;


 [System.Data.Linq.Mapping.DatabaseAttribute(Name="Database1")]
 public partial class DataClasses1DataContext : System.Data.Linq.DataContext
 {

  private static System.Data.Linq.Mapping.MappingSource mappingSource = new AttributeMappingSource();

    #region Extensibility Method Definitions
    partial void OnCreated();
    partial void InsertPerson(Person instance);
    partial void UpdatePerson(Person instance);
    partial void DeletePerson(Person instance);
    #endregion

  public DataClasses1DataContext() : 
    base(global::System.Configuration.ConfigurationManager.ConnectionStrings["Database1ConnectionString"].ConnectionString, mappingSource)
  {
   OnCreated();
  }

  public DataClasses1DataContext(string connection) : 
    base(connection, mappingSource)
  {
   OnCreated();
  }

  public DataClasses1DataContext(System.Data.IDbConnection connection) : 
    base(connection, mappingSource)
  {
   OnCreated();
  }

  public DataClasses1DataContext(string connection, System.Data.Linq.Mapping.MappingSource mappingSource) : 
    base(connection, mappingSource)
  {
   OnCreated();
  }

  public DataClasses1DataContext(System.Data.IDbConnection connection, System.Data.Linq.Mapping.MappingSource mappingSource) : 
    base(connection, mappingSource)
  {
   OnCreated();
  }

  public System.Data.Linq.Table<Person> Persons
  {
   get
   {
    return this.GetTable<Person>();
   }
  }
 }

 [Table(Name="dbo.Persons")]
 public partial class Person : INotifyPropertyChanging, INotifyPropertyChanged
 {

  private static PropertyChangingEventArgs emptyChangingEventArgs = new PropertyChangingEventArgs(String.Empty);

  private int _PersonID;

  private string _FirstName;

  private string _LastName;

  private string _Age;

    #region Extensibility Method Definitions
    partial void OnLoaded();
    partial void OnValidate(System.Data.Linq.ChangeAction action);
    partial void OnCreated();
    partial void OnPersonIDChanging(int value);
    partial void OnPersonIDChanged();
    partial void OnFirstNameChanging(string value);
    partial void OnFirstNameChanged();
    partial void OnLastNameChanging(string value);
    partial void OnLastNameChanged();
    partial void OnAgeChanging(string value);
    partial void OnAgeChanged();
    #endregion

  public Person()
  {
   OnCreated();
  }

  [Column(Storage="_PersonID", AutoSync=AutoSync.OnInsert, DbType="Int NOT NULL IDENTITY", IsPrimaryKey=true, IsDbGenerated=true)]
  public int PersonID
  {
   get
   {
    return this._PersonID;
   }
   set
   {
    if ((this._PersonID != value))
    {
     this.OnPersonIDChanging(value);
     this.SendPropertyChanging();
     this._PersonID = value;
     this.SendPropertyChanged("PersonID");
     this.OnPersonIDChanged();
    }
   }
  }

  [Column(Storage="_FirstName", DbType="NChar(10)")]
  public string FirstName
  {
   get
   {
    return this._FirstName;
   }
   set
   {
    if ((this._FirstName != value))
    {
     this.OnFirstNameChanging(value);
     this.SendPropertyChanging();
     this._FirstName = value;
     this.SendPropertyChanged("FirstName");
     this.OnFirstNameChanged();
    }
   }
  }

  [Column(Storage="_LastName", DbType="NChar(10)")]
  public string LastName
  {
   get
   {
    return this._LastName;
   }
   set
   {
    if ((this._LastName != value))
    {
     this.OnLastNameChanging(value);
     this.SendPropertyChanging();
     this._LastName = value;
     this.SendPropertyChanged("LastName");
     this.OnLastNameChanged();
    }
   }
  }

  [Column(Storage="_Age", DbType="NChar(10)")]
  public string Age
  {
   get
   {
    return this._Age;
   }
   set
   {
    if ((this._Age != value))
    {
     this.OnAgeChanging(value);
     this.SendPropertyChanging();
     this._Age = value;
     this.SendPropertyChanged("Age");
     this.OnAgeChanged();
    }
   }
  }

  public event PropertyChangingEventHandler PropertyChanging;

  public event PropertyChangedEventHandler PropertyChanged;

  protected virtual void SendPropertyChanging()
  {
   if ((this.PropertyChanging != null))
   {
    this.PropertyChanging(this, emptyChangingEventArgs);
   }
  }

  protected virtual void SendPropertyChanged(String propertyName)
  {
   if ((this.PropertyChanged != null))
   {
    this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
   }
  }
 }
}
#pragma warning restore 1591

PersonRepository.cs:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations;
using System.Web.Mvc;
using Validate.Models;

namespace Validate.Models
{
    [MetadataType(typeof(Person_Validation))]
    public partial class Person
    {
    }

    public class Person_Validation 
    {
        [Required]
        string FirstName { get; set; }

        [Required]
        string LastName { get; set; }

        [Required]
        int Age { get; set; }
    }

    public class PersonRepository
    {
        private DataClasses1DataContext db = new DataClasses1DataContext();

        public IQueryable<Person> FindAllPersons()
        {
            return db.Persons;
        }

        public Person GetPerson(int id)
        {
            return db.Persons.SingleOrDefault(x => x.PersonID == id);
        }

        public void Add(Person person)
        {
            db.Persons.InsertOnSubmit(person);
        }

        public void Delete(Person person)
        {
            db.Persons.DeleteOnSubmit(person);
        }

        public void Save()
        {
            db.SubmitChanges();
        }
    }
}

/Views/Person/Create.aspx:

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

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

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

    <h2>Create</h2>

    <%= ViewData["greska"]%>

    <% using (Html.BeginForm()) {%>
        <%= Html.ValidationSummary(true) %>

        <fieldset>
            <legend>Fields</legend>           

            <div class="editor-label">
                <%= Html.LabelFor(model => model.FirstName) %>
            </div>
            <div class="editor-field">
                <%= Html.TextBoxFor(model => model.FirstName) %>
                <%= Html.ValidationMessageFor(model => model.FirstName) %>
            </div>

            <div class="editor-label">
                <%= Html.LabelFor(model => model.LastName) %>
            </div>
            <div class="editor-field">
                <%= Html.TextBoxFor(model => model.LastName) %>
                <%= Html.ValidationMessageFor(model => model.LastName) %>
            </div>

            <div class="editor-label">
                <%= Html.LabelFor(model => model.Age) %>
            </div>
            <div class="editor-field">
                <%= Html.TextBoxFor(model => model.Age) %>
                <%= Html.ValidationMessageFor(model => model.Age) %>
            </div>

            <p>
                <input type="submit" value="Create" />
            </p>
        </fieldset>

    <% } %>

    <div>
        <%= Html.ActionLink("Back to List", "Index") %>
    </div>

</asp:Content>

Answer 1

一种方法是使用 MetadataTypeAttribute .该属性允许您将“伙伴”类关联到您的 LINQ2SQL 类。伙伴类包含与原始类相同的属性，但 ASP.NET MVC 将从伙伴类读取验证属性。引入 MetadataTypeAttribute 是因为 C# 不允许您添加在基类中定义的属性 - 因此会出现错误。

以下示例复制自MSDN :

[MetadataType(typeof(CustomerMetaData))]
public partial class Customer
{
}

public class CustomerMetaData
{
    // Apply RequiredAttribute
    [Required(ErrorMessage = "Title is required.")]
    public object Title { get; set; }
}

---

编辑:

我不确定您的操作实现是否正确。当您的模型状态无效时，您想再次显示“创建” View 。改为尝试以下方法:

[HttpPost]
public ActionResult Create(Person person, FormCollection collection)
{
    if (ModelState.IsValid)
    {
        try
        {
            personRepository.Add(person);
            personRepository.Save();
            return RedirectToAction("Index");            
        }
        catch
        {
            return View(person);
        }
    }
    else
        return View(person);     
}

---

编辑 2:

Linq2Sql 已经为您创建了一个部分的 Person 类，它应该是这样的。当您创建自己的部分 Person 类时，编译器会将您的类定义与 Linq2Sql 创建的类定义合并为一个 Person 类。但是，这两个分部类定义在同一个程序集中 和在同一个命名空间 是非常重要的。因此，请确保您已将部分 Person 类定义放在与 Linq2Sql Person 类相同的命名空间中。

---

编辑 3:

我突然想到您的 Person_Validation 类的属性是私有(private)的。他们需要公开。希望对您有所帮助:-)