public void Delete(App.Models.Domain.SheetEntry item)
 {
     if (item != null)
     {
         this._entitySet.Remove(item);
     }
 }
 public void DeleteById(int id)
 {
     App.Models.Domain.SheetEntry item = this.FindById(id);
     if (item != null)
     {
         this._entitySet.Remove(item);
     }
 }
 public void Add(App.Models.Domain.SheetEntry item)
 {
     this._entitySet.Add(item);
 }