/* (CLIENT-WINS) OVERRIDING: Resolving optimistic concurrency exceptions as Client-Wins */
// The override method can be used to override persisted data with the supplied entity data.
public void UpdateCustomerOverride(Customer customer)
{
bool saveFailed;
this.context.Entry(customer).State = EntityState.Modified;
do
{
saveFailed = false;
try
{
this.context.SaveChanges();
}
catch (DbUpdateConcurrencyException e)
{
saveFailed = true;
// Each entry has three distinct sets of values,
// CurrentValues (The values currently contained in the entity)
// OriginalValues (The values read from the database upon commitment)
// DatabaseValues (The values currently persisted in the database)
// Set the original values of the entity to the values stored in the database
// avoiding another exception with regards to concurrency.
var entry = e.Entries.Single();
entry.OriginalValues.SetValues(entry.GetDatabaseValues());
}
} while (saveFailed);
}
public void InsertCustomer(Customer customer)
{
////AfterHandInChange - attach battery in order not to insert a duplicate battery
if (customer.Battery != null)
{
this.context.Batteries.Attach(customer.Battery);
}
this.context.Customers.Add(customer);
}
public void UpdateCustomer(Customer customer)
{
try
{
this.customerRepository.UpdateCustomer(customer);
this.customerRepository.Save();
}
catch (DbUpdateConcurrencyException e)
{
throw new FaultException(e.Message);
}
catch (Exception e)
{
throw new FaultException(e.Message);
}
}
public void InsertCustomer(string name, string streetAddress, string phoneNr, string zipCodeID, int batteryId)
{
////AfterHandInChange - update battery
BatteryCtr batteryCtr = new BatteryCtr();
var battery = batteryCtr.FindBattery(batteryId);
var customer = new Customer
{
Name = name,
StreetAddress = streetAddress,
PhoneNr = phoneNr,
ZipCodeNumber = zipCodeID,
BatteryId = batteryId,
Battery = battery
};
////AfterHandInChange - update battery
battery.BatteryStation = null;
battery.BatteryStationID = null;
batteryCtr.UpdateBattery(battery);
this.customerRepository.InsertCustomer(customer);
this.customerRepository.Save();
}
public void UpdateCustomer(Customer customer)
{
controller.UpdateCustomer(customer);
}
public void UpdateCustomer(Customer customer)
{
this.context.Entry(customer).State = EntityState.Modified;
}
/* (DATABASE-WINS) RELOADING: Resolving optimistic concurrency exceptions with Reload */
// The Reload method can be used to override the values contained in the entity,
// and can be designed to return a new entity containing persisted data to the caller.
public Customer UpdateCustomerReload(Customer customer)
{
bool saveFailed;
do
{
saveFailed = false;
this.context.Entry(customer).State = EntityState.Modified;
try
{
this.context.SaveChanges();
}
catch (DbUpdateConcurrencyException e)
{
saveFailed = true;
// Update the supplied customer with persisted data
e.Entries.Single().Reload();
}
} while (saveFailed);
return customer;
}
/* (CLIENT-CHOOSES) OVERRIDING: Resolving optimistic concurrency exception as Client-Choses */
// The override method can be used to override persisted data, on behest of the client.
public void UpdateCustomerOverrideClientChooses(Customer customer)
{
bool saveFailed;
this.context.Entry(customer).State = EntityState.Modified;
do
{
saveFailed = false;
try
{
this.context.SaveChanges();
}
catch (DbUpdateConcurrencyException e)
{
saveFailed = true;
// Get the current entity
var entry = e.Entries.Single();
// Get the current values for the entity
var currentValues = entry.CurrentValues;
// Get the persisted values from the database
var databaseValues = entry.GetDatabaseValues();
// Choose an initial set of resolved values. In this case
// make the default be the values currently in the database.
var resolvedValues = databaseValues.Clone();
// Have the client choose what the resolved values should be
HaveUserResolveConcurrency(currentValues, databaseValues,
resolvedValues);
// Update the original values with the database values and
// the current values with whatever the client choose.
entry.OriginalValues.SetValues(databaseValues);
entry.CurrentValues.SetValues(resolvedValues);
}
} while (saveFailed);
}
