如何在实体框架实体上实现INotifyPropertyChanged [英] How to Implement INotifyPropertyChanged on Entity Framework Entity

问题描述

它有一个属性AccountTypeId。

当它更改时，我需要一个通知，因此可以更新其他字段。

这样做通常如何？这只需要一个属性，所以我不想使用修改的模板。

AccountTypeId绑定到WinForms中的用户界面中的ComboBox，所以它不是真的是一个MVVM应用程序，我通常会在WPF中。

解决方案

一种方法是去EDMX并重命名该字段AccountTypeID_Internal（例如），并且在EDMX中将属性设置为 Private 。然后创建一个Partial Class。

生成的Account.cs应如下所示：

  // --------------------------------------------- --------------------------------- 
 //<自动生成> 
 //该代码是从模板生成的。 
 // 
 //手动更改此文件可能会导致应用程序出现意外的行为。 
 //如果重新生成代码，则对该文件的手动更改将被覆盖。 
 //< / auto-generated> 
 // -------------------------------------------- ---------------------------------- 
 
命名空间< yournamespace> 
 {
 using System; 
使用System.Collections.Generic; 
 
 public partial class Account 
 {
 private int AccountTypeId_Internal {get;组; } 
 
 //其他自动生成的属性
} 
} 
  

Account.Partial.Cs

  public partial class Account：INotifyPropertyChanged 
 {
 public Int AccountTypeId 
 {
 get 
 {
 return this.AccountTypeId_Internal; 
} 
 set 
 {
 this.AccountTypeId_Internal = value; 
 //做INotifyPropertyChangedLogic 
} 
} 
 
 //实现INotifyPropertyChanged 
} 
  

这样做的优点是您已经编写的代码完全不需要更改。缺点是如果从edmx中删除Accout并重新添加它，则必须再次执行edmx步骤。

I have an EF 5 entity called Account generated with the standard template.

It has a property AccountTypeId.

When it changes, I need a notification so another field can be updated.

How is this typically done? This is needed for only one property, so I don't want to use a modified template.

AccountTypeId is bound to a ComboBox in the UI in WinForms, so it's not really an MVVM app as I would normally do in WPF.

解决方案

One way is to go to the EDMX and rename the field to AccountTypeID_Internal (for example), and in the EDMX set the property to Private. Then create a Partial Class.

Generated Account.cs should look like:

//------------------------------------------------------------------------------
// <auto-generated>
//    This code was generated from a template.
//
//    Manual changes to this file may cause unexpected behavior in your application.
//    Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace <yournamespace>
{
    using System;
    using System.Collections.Generic;

    public partial class Account
    {
        private int AccountTypeId_Internal  { get; set; }

        // other auto generated properties
    }
}

Account.Partial.Cs

public partial class Account : INotifyPropertyChanged
{
  public Int AccountTypeId
  {
    get
    {
      return this.AccountTypeId_Internal;
    }
    set
    {
      this.AccountTypeId_Internal = value;
      // Do INotifyPropertyChangedLogic
    }
  }

  // Implement INotifyPropertyChanged
}

The advantage of this is that your already written code doesn't have to change at all. The downside is that if you remove the Accout from the edmx and re-add it you will have to go through the edmx steps again.

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