public int Add(Region region)
{
// TODO: Add Unit Test
if (region == null)
throw new ArgumentNullException("region", "region is null.");
using (var dbContext = new NWContext())
{
/* NOTE:
* The TerritoryID column in Territories is a string - nvarchar(20) - rather than an integer.
* The existing data in Northwind Traders uses the zip code of the city/town as the TerritoryID.
* This sample just "simplifies" and assigns the territory description as the ID, since we're
* in Canada and we aren't using a single zip or postal code.
*/
foreach (var territory in region.Territories)
if (string.IsNullOrEmpty(territory.TerritoryID))
territory.TerritoryID = territory.TerritoryDescription;
/* NOTE:
* The RegionID column in Regions is an integer, but it is not an IDENTITY column.
* As such, we're simply going to get the next highest ID available.
*/
if (region.RegionID <= 0)
region.RegionID = dbContext.Regions.Max(item => item.RegionID) + 1;
dbContext.Regions.Add(region);
dbContext.SaveChanges();
return region.RegionID;
}
}
public int AddShipper(Shipper info)
{
using (var context = new NWContext())
{
context.Shippers.Add(info);
context.SaveChanges();
return info.ShipperID;
}
}
public int AddProduct(Product info)
{
using (var context = new NWContext())
{
context.Products.Add(info);
context.SaveChanges();
return info.ProductID;
}
}
public void DeleteProduct(Product product)
{
using (var context = new NWContext())
{
var found = context.Products.Find(product.ProductID);
if (found != null)
{
context.Products.Remove(found);
context.SaveChanges();
}
}
}
public void DeleteShipper(Shipper shipper)
{
using (var context = new NWContext())
{
//BEST practice. find shipper first, then delete
var found = context.Shippers.Find(shipper.ShipperID);
if (found != null)
{
context.Shippers.Remove(found);
context.SaveChanges();
}
}
}
public void UpdateShipper(Shipper info)
{
//Note: see question and commentary on
//http://stackoverflow.com/questions/15336248/entity-framework-5-updating-a-reocrd
using (var context = new NWContext())
{
context.Shippers.Attach(info);
context.Entry(info).State = EntityState.Modified;
context.SaveChanges();
}
}
public void UpdateProduct(Product info)
{
using (var context = new NWContext())
{
context.Products.Attach(info);
context.Entry(info).State = EntityState.Modified;
context.SaveChanges();
}
}
public void Update(Region region, List<Territory> territories)
{
// TODO: Add Unit Test
if (region == null)
throw new ArgumentNullException("region", "region is null.");
if (territories == null)
throw new ArgumentNullException("territories", "territories is null.");
using (var dbContext = new NWContext())
{
foreach (var item in territories)
{
var found = dbContext.Territories.Find(item.TerritoryID);
if (found != null)
{
/* NOTE:
* Pre-process the Territory IDs to see if they should be "synced" with the name/description.
* This will be the case if, in the original, the ID was the same as the description
*/
string foundTerritoryID = found.TerritoryID;
string foundTerritoryDescription = found.TerritoryDescription.Trim(); // HACK: Turns out, the column is nchar(50), not an nvarchar....
string itemTerritoryID = item.TerritoryID;
string itemTerritoryDescription = item.TerritoryDescription.Trim();
if (foundTerritoryID.Equals(foundTerritoryDescription) &&
!itemTerritoryID.Equals(itemTerritoryDescription))
{
item.TerritoryID = itemTerritoryDescription;
dbContext.Territories.Remove(found); // Because the PK has changed...
dbContext.Territories.Add(item); // Because the PK has changed...
}
}
}
dbContext.Entry(region).State = EntityState.Modified;
dbContext.SaveChanges();
}
}