private static Manufacturer CreateManufacturerIfNotExists(PhotographySystemEntities context, XElement xManufacturer)
{
Manufacturer manufacturer = null;
var xManifName = xManufacturer.Element("manufacturer-name");
if (xManifName != null)
{
var manifacName = xManifName.Value;
manufacturer = context.Manufacturers.FirstOrDefault(m => m.Name == manifacName);
if (manufacturer != null)
{
Console.WriteLine("Existing manufacturer: {0}", manifacName);
}
else
{
manufacturer = new Manufacturer
{
Name = manifacName
};
context.Manufacturers.Add(manufacturer);
context.SaveChanges();
Console.WriteLine("Created manufacturer: {0}", manifacName);
}
}
return manufacturer;
}
private static void CreateLensesIfNotExist(PhotographySystemEntities context, IEnumerable<XElement> xLenses, Manufacturer manufacturer)
{
foreach (var xLense in xLenses)
{
var lensModel = xLense.Attribute("model").Value;
var lensType = xLense.Attribute("type").Value;
var lensPrice = xLense.Attribute("price");
var lens = context.Lenses.FirstOrDefault(l => l.Model == lensModel);
if (lens != null)
{
Console.WriteLine("Existing lens: {0}", lensModel);
}
else
{
lens = new Lens
{
Model = lensModel,
Type = lensType,
Price = lensPrice != null ? decimal.Parse(lensPrice.Value) : default(decimal?),
ManufacturerId = manufacturer.Id
};
context.Lenses.Add(lens);
context.SaveChanges();
Console.WriteLine("Created lens: {0}", lensModel);
}
}
}
static void Main()
{
var context = new PhotographySystemEntities();
var xmlDocument = XDocument.Load("../../manufacturers-and-goods.xml");
var manufacturers =
from manufacturer in xmlDocument.Descendants("manufacturer")
select new
{
Name = manufacturer.Attribute("name").Value,
Cameras =
from camera in xmlDocument.Descendants("camera")
select new
{
Model =
camera.Attribute("model") == null ?
null :
camera.Attribute("model").Value,
Year =
camera.Attribute("year") == null ?
null :
camera.Attribute("year").Value,
Price =
camera.Attribute("price") == null ?
(decimal?)null :
decimal.Parse(camera.Attribute("price").Value),
Megapixels =
camera.Attribute("megapixels") == null ?
(int?)null :
int.Parse(camera.Attribute("megapixels").Value)
},
Lenses =
from lens in xmlDocument.Descendants("lens")
select new
{
Model =
lens.Attribute("model") == null ?
null :
lens.Attribute("model").Value,
Type =
lens.Attribute("type") == null ?
null :
lens.Attribute("type").Value,
Price =
lens.Attribute("price") == null ?
(decimal?)null :
decimal.Parse(lens.Attribute("price").Value)
}
};
foreach (var manufacturer in manufacturers)
{
if (context.Manufacturers.Any(m => m.Name == manufacturer.Name))
{
Console.WriteLine(
"Manufacturer {0} already exists.",
manufacturer.Name
);
}
else
{
var newManufacturer = new Manufacturer()
{
Name = manufacturer.Name
};
context.Manufacturers.Add(newManufacturer);
context.SaveChanges();
Console.WriteLine(
"Successfully added manufacturer {0}.",
manufacturer.Name
);
using (var transaction = context.Database.BeginTransaction())
{
try
{
int cameraYear = 0;
foreach (var camera in manufacturer.Cameras)
{
if (camera.Year != null)
{
cameraYear = int.Parse(camera.Year);
}
context.Cameras.Add(new Camera()
{
Model = camera.Model,
Year = cameraYear,
Price = camera.Price,
Megapixels = camera.Megapixels,
ManufacturerId = newManufacturer.Id
});
}
foreach (var lens in manufacturer.Lenses)
{
context.Lenses.Add(new Lens()
{
Model = lens.Model,
Type = lens.Type,
Price = lens.Price,
ManufacturerId = newManufacturer.Id
});
}
context.SaveChanges();
transaction.Commit();
}
catch (DbEntityValidationException)
{
transaction.Rollback();
}
}
}
}
}
