public object GetCategories()
{
object result;
using (NorthwindDataContext _context = new NorthwindDataContext())
{
var categoryTbl = _context.LinqCategories;
result = categoryTbl.ToList();//<= ideea este ca atunci cand folosim context-ul asa in using, la final cheama metoda Dispose si atunci ca sa ne ramana contextul in salvam intr-un obiect lista ce il vom returna
}
return(result);
}
/// <summary>
/// trebuie sa salvam automat dupa ce adaugam un produs, altfel using o sa cheme metoda Dispose si nu va fi salbat produsul
/// </summary>
/// <param name="_context"></param>
private void Save(NorthwindDataContext _context)
{
try
{
_context.SubmitChanges();
}
catch (Exception e)
{
MessageBox.Show(e.Message);
throw;
}
}
public object GetProducts(int categoryID)
{
object result;
using (NorthwindDataContext _context = new NorthwindDataContext())
{
var productsTbl = from p in _context.LinqProducts
where p.CategoryId == categoryID
select p;
result = productsTbl.ToList();
}
return(result);
}
/// <summary>
/// metoda asta va avea grija sa nu iterez acelasi id in mai multe produse
/// </summary>
/// <param name="_context"></param>
/// <returns></returns>
private static int GetNextID(NorthwindDataContext _context)
{
int _idNext = _context.LinqProducts.Count() + 1;
foreach (var item in _context.LinqProducts)
{
if (_idNext <= item.CategoryId)
{
_idNext++;
}
}
return(_idNext);
}
public void DeleteProduct(BindingSource bidingSource, int productID)
{
using (NorthwindDataContext _context = new NorthwindDataContext())
{
var querryProduct = from p in _context.LinqProducts
where p.ProductID == productID
select p;
LinqProduct linqProd = querryProduct.Single();
_context.LinqProducts.DeleteOnSubmit(linqProd);
Save(_context);
// bidingSource.Remove(linqProd);
}
}
public void Save()
{
using (NorthwindDataContext _context = new NorthwindDataContext())
{
try
{
_context.SubmitChanges();
}
catch (Exception e)
{
MessageBox.Show(e.Message);
throw;
}
}
}
public void AddProduct(BindingSource bidingSource, Product product)
{
using (NorthwindDataContext _context = new NorthwindDataContext())
{
LinqProduct linqProd = new LinqProduct();
//copiem valorile din produs in produsul linq
linqProd.CategoryId = product.CategoryId;//TO DO: asta mai are
int _idNext = GetNextID(_context);
linqProd.ProductID = _idNext;
linqProd.Discontinued = product.Discontinued;
linqProd.ProductName = product.ProductName;
linqProd.QuantityPerUnit = product.QuantityPerUnit;
linqProd.UnitPrice = product.UnitPrice;
linqProd.UnitsInStock = product.UnitsInStock;
linqProd.UnitsOnOrder = product.UnitsOnOrder;
//acum adaugam in contextul nostru/in tabelul nostru, produsul
_context.LinqProducts.InsertOnSubmit(linqProd);
bidingSource.Add(linqProd);
Save(_context);
}
}