public static void InsertCustomer(NorthwindEntities northDb,
string companyName = null,
string contractName = null,
string contractTitle = null,
string address = null,
string city = null,
string region = null,
string postalCode = null,
string country = null,
string phone = null,
string fax = null)
{
using (northDb)
{
Customer newCustomer = new Customer();
newCustomer.CustomerID = "temporaryUnique";
newCustomer.CompanyName = companyName;
newCustomer.ContactName = contractName;
newCustomer.ContactTitle = contractTitle;
newCustomer.Address = address;
newCustomer.City = city;
newCustomer.Region = region;
newCustomer.PostalCode = postalCode;
newCustomer.Country = country;
newCustomer.Phone = phone;
newCustomer.Fax = fax;
northDb.Customers.Add(newCustomer);
northDb.SaveChanges();
}
}
public static void UpdateCustomer(NorthwindEntities northDb, string id, string companyName)
{
using (northDb)
{
Customer customerToUpdate = (Customer)northDb.Customers.Select(x => x.CustomerID == id);
customerToUpdate.CompanyName = companyName;
northDb.SaveChanges();
}
}
public static void DeleteCustomer(NorthwindEntities northDb, string id)
{
using (northDb)
{
Customer customerToDelete = (Customer)northDb.Customers.Select(x => x.CustomerID == id);
northDb.Customers.Remove(customerToDelete);
northDb.SaveChanges();
}
}
private static void Main()
{
Console.WriteLine("-- Establishing first connection to database Northwind...");
Thread.Sleep(1000);
using (var firstDb = new NorthwindEntities())
{
var firstCategory = firstDb.Categories.Find(4);
Console.WriteLine("Initial category description: {0}", firstCategory.Description);
Thread.Sleep(1000);
firstCategory.Description = "Cheese and many more";
Console.WriteLine("Category description after changing: {0}", firstCategory.Description);
Thread.Sleep(1000);
Console.WriteLine("-- Establishing second connection to database Northwind...");
Thread.Sleep(1000);
using (var secondDb = new NorthwindEntities())
{
var secondCategory = secondDb.Categories.Find(4);
Console.WriteLine("Initial category description: {0}", secondCategory.Description);
Thread.Sleep(1000);
secondCategory.Description = "Cheese and many, many more";
Console.WriteLine("Category description after changing: {0}", secondCategory.Description);
Thread.Sleep(1000);
firstDb.SaveChanges();
secondDb.SaveChanges();
Console.WriteLine("Category description after saving: {0}", secondCategory.Description);
Thread.Sleep(1000);
}
Console.WriteLine("-- Closing second connection to the database...");
Thread.Sleep(1000);
Console.WriteLine("Category description after saving: {0}", firstCategory.Description);
Thread.Sleep(1000);
}
Console.WriteLine("-- Closing first connection to the database...");
using (var db = new NorthwindEntities())
{
Console.WriteLine("Actual result: {0}", db.Categories.Find(4).Description);
}
}
