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Дмитрий Валерьевич
Asked:2020-08-15 15:19:54 +0000 UTC2020-08-15 15:19:54 +0000 UTC

WPF 数据网格。保存对实体框架的更改

  • 772

将数据加载到 DataGrid 中 var result = db.Sports.AsEnumerable().ToList(); dataGrid.ItemsSource = result;

显示数据。编辑好后存回实体框架。
db.SaveChanges(); 仅保存更改的数据，不保存新添加或删除的数据。

  public class Sports : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;
    private string _sport;

    public string sport
    {
        get
        {
            return _sport;
        }
        set
        {
            _sport = value;
            OnPropertyChanged("sport");
        }
    }

    [Key, DatabaseGenerated(DatabaseGeneratedOption.None)]
    public int sports_code { get; set; }

    protected void OnPropertyChanged(string name)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null)
        {
            handler(this, new PropertyChangedEventArgs(name));
        }
    }      
}
c#

1 个回答

  1. Best Answer

    Sports objToAdd; // 获取被改变的对象

     private void dataGrid_SelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        objToAdd = dataGrid.SelectedItem as Sports;

        //Проверим если такой же в сущности:
        var conn = db.Sports.Where(c => c.sports_code == objToAdd.sports_code).FirstOrDefault();
        if (conn == null)
        {                       
            db.Sports.Add(objToAdd);
        }
        else
        {
            conn.sports_code = objToAdd.sports_code;
            conn.sport = objToAdd.sport;
            db.Entry(conn).State = System.Data.Entity.EntityState.Modified;
        }
        db.SaveChanges();
    }

    我在这里找到了提示

    • 3

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