Working with Object Services - Entity Framework 6 Recipes - page 253

context.Accounts.Add(account1);
context.Accounts.Add(account2);
context.Accounts.Add(account3);
context.SaveChanges();
// Add monthly service charges for each account.
foreach (var account in context.Accounts)
{
var transactions = new List<Transaction>
{
new Transaction
{
TransactionDate = Convert.ToDateTime("08/09/2013"),
Amount = -5.00M
},
new Transaction
{
TransactionDate = Convert.ToDateTime("08/09/2013"),
Amount = -2.00M
}
};
Task saveTask = SaveAccountTransactionsAsync(account.AccountNumber, transactions);
Console.WriteLine("Account Transactions for the account belonging to {0}
(acct# {1})", account.AccountHolder, account.AccountNumber);
await saveTask;
await ShowAccountTransactionsAsync(account.AccountNumber);
}
}
}
private static async Task SaveAccountTransactionsAsync(int accountNumber,
ICollection<Transaction> transactions)
{
using (var context = new EF6RecipesContext())
{
var account = new Account { AccountNumber = accountNumber };
context.Accounts.Attach(account);
context.Entry(account).Collection(a => a.Transactions).Load();
foreach (var transaction in transactions.OrderBy(t => t.TransactionDate))
{
account.Transactions.Add(transaction);
}
await context.SaveChangesAsync();
}
}