datagridview绑定到实体不更新数据库 [英] datagridview binding to entity not updating database

问题描述

我正在从一个实体对象填充一个网格，它正在显示数据。当我进行更改并将其保存回来时，没有任何更新。

这是我的代码：

在我的加载事件：

  var query = from c in _entities.PaymentTypes 
其中c.CorporationId == _currentcorp.CorporationId 
选择
 new DataBindingProjection 
 {
 PaymentTypeId = c.PaymentTypeId，
 CorporationId = c.CorporationId，
 TokenId = c.TokenId，
 IsActive = c.IsActive，
描述= c.Description，
 CashChargeCodeType = c.CashChargeCodeType，
 SortOrder = c.SortOrder，
 ExcludeCreditCode = c.ExcludeCreditCodes，
已更新= c.IsUpdated，
 IsAdded = c.IsAdded，
 ClearUpdatedAndAdded = c.ClearUpdateAndAdded 
 }; 
 dataGridView_PaymentTypes.DataSource = query.ToList（）; 
  

我的课程：

  private class DataBindingProjection 
 {
 public Guid PaymentTypeId {get;组; } 
 public Guid CorporationId {get;组; } 
 public Guid TokenId {get;组; } 
 public bool IsActive {get;组; } 
 public string描述{get;组; } 
 public int CashChargeCodeType {get;组; } 
 public int SortOrder {get;组; } 
 public int ExcludeCreditCode {get;组; } 
 public bool IsUpdated {get;组; } 
 public bool IsAdded {get;组; } 
 public bool ClearUpdatedAndAdded {get;组; 
} 
  

在保存更改的按钮中：

  private void button_SaveChanges2_Click（object sender，EventArgs e）
 {
 button_SaveChanges2.Enabled = false; 
 _entities.SaveChanges（）; 
 timer1.Enabled = true; 
 button_SaveChanges2.Enabled = true; 
} 
  

我做错了什么？

响应bmused：

在课程级别定义：

  private SuburbanPortalEntities _entities; 
  

在我的加载中定义：

  var bs = new BindingSource（）; 
 _entities.PaymentTypes.Where（x => x.CorporationId == _currentcorp.CorporationId）.Load; 
 bs.DataSource = _entities.PaymentTypes.Local.ToBindingList（）; 
 dataGridView_PaymentTypes.DataSource = bs; 
  

它显示无法加载符号加载和本地：

解决方案

使用Winforms和Entity Framework进行双向数据绑定可以通过从 DbContext c中创建一个 IBindinglist / code> 本地 ObservableCollection< T> 并将其设置为 DataSource 一个 BindingSource 。例如：

  private BindingSource bs = new BindingSource（）; 
 private MyDbContext context = new MyDbContext（）; 
 
 context.MyEntities.Where（x => x.SomeProperty == 2）.Load（）; 
 bs.DataSource = context.MyEntities.Local.ToBindingList（）; 
 myDataGridView.DataSource = bs; 
  




I am populating a grid from a entity object and it is displaying the data fine. When I make changes and save it back, nothing is updating.

Here is my code:

In my load event:

  var query = from c in _entities.PaymentTypes
              where c.CorporationId == _currentcorp.CorporationId
              select
                new DataBindingProjection
                  {
                    PaymentTypeId = c.PaymentTypeId,
                    CorporationId = c.CorporationId,
                    TokenId = c.TokenId,
                    IsActive = c.IsActive,
                    Description = c.Description,
                    CashChargeCodeType = c.CashChargeCodeType,
                    SortOrder = c.SortOrder,
                    ExcludeCreditCode = c.ExcludeCreditCodes,
                    IsUpdated = c.IsUpdated,
                    IsAdded = c.IsAdded,
                    ClearUpdatedAndAdded = c.ClearUpdateAndAdded
                  };
  dataGridView_PaymentTypes.DataSource = query.ToList();

My class:

private class DataBindingProjection
{
  public Guid PaymentTypeId { get; set; }
  public Guid CorporationId { get; set; }
  public Guid TokenId { get; set; }
  public bool IsActive { get; set; }
  public string Description { get; set; }
  public int CashChargeCodeType { get; set; }
  public int SortOrder { get; set; }
  public int ExcludeCreditCode { get; set; }
  public bool IsUpdated { get; set; }
  public bool IsAdded { get; set; }
  public bool ClearUpdatedAndAdded { get; set; }
}

In the button to save the changes:

private void button_SaveChanges2_Click(object sender, EventArgs e)
{
  button_SaveChanges2.Enabled = false;
  _entities.SaveChanges();
  timer1.Enabled = true;
  button_SaveChanges2.Enabled = true;
}

What am I doing wrong?

In response to bmused:

Defined at the class level:

private SuburbanPortalEntities _entities;

defined in my load:

  var bs = new BindingSource();
  _entities.PaymentTypes.Where(x => x.CorporationId == _currentcorp.CorporationId).Load;
  bs.DataSource = _entities.PaymentTypes.Local.ToBindingList();
  dataGridView_PaymentTypes.DataSource = bs;

It is showing that it cannot load symbol Load and Local:

解决方案

Two-way databinding with Winforms and Entity Framework can be achieved by creating an IBindinglist from the DbContext Local ObservableCollection<T> and setting it as the DataSource of a BindingSource. Example:

private BindingSource bs = new BindingSource();
private MyDbContext context = new MyDbContext();

context.MyEntities.Where(x=>x.SomeProperty == 2).Load(); 
bs.DataSource = context.MyEntities.Local.ToBindingList(); 
myDataGridView.DataSource = bs;

这篇关于datagridview绑定到实体不更新数据库的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！