public static bool TryWithdraw(ATMContext dbContext, string cardNumber, decimal amount, string PIN)
{
var success = false;
var transactionOptions = new TransactionOptions() { IsolationLevel = IsolationLevel.RepeatableRead };
using (var scope = new TransactionScope(TransactionScopeOption.RequiresNew, transactionOptions))
{
var cardQuery =
from c in dbContext.CardAccounts
where c.CardNumber == cardNumber
select c;
var card = cardQuery.FirstOrDefault();
if (card != null &&
card.CardPIN == PIN &&
card.CardCash >= amount)
{
card.CardCash -= amount;
success = true;
scope.Complete();
}
}
if (success)
{
RecordWithdraw(dbContext , cardNumber, amount);
dbContext.SaveChanges();
return true;
}
return false;
}
public static void Main()
{
Database.SetInitializer(new MigrateDatabaseToLatestVersion<ATMContext, Configuration>());
Console.WriteLine("Before");
ListAcounts();
var cardNumber = "1234567890";
var amount = 5500m;
var pin = "1234";
var success = false;
using (var dbContext = new ATMContext())
{
// Force Initialization
// Comment seed once records are inserted
dbContext.Database.Initialize(true);
success = TryWithdraw(dbContext, cardNumber, amount, pin);
}
Console.WriteLine("Withdraw {0}", success ? "succeeded" : "failed");
Console.WriteLine("After");
ListAcounts();
}
public static void RecordWithdraw(ATMContext dbContext, string cardNumber, decimal ammount)
{
var transactionOptions = new TransactionOptions() { IsolationLevel = IsolationLevel.RepeatableRead };
using (var scope = new TransactionScope(TransactionScopeOption.RequiresNew, transactionOptions))
{
var newRecord = new TransactionHistory()
{
TransactionDate = DateTime.Now,
Ammount = ammount,
CardNumber = cardNumber
};
dbContext.TransactionsHistory.Add(newRecord);
scope.Complete();
}
}
public static void ListAcounts()
{
using (var dbContext = new ATMContext())
{
foreach (var account in dbContext.CardAccounts)
{
Console.WriteLine("Account ID: {0}, Amount: {1}", account.Id, account.CardCash);
}
}
}