/// <summary>
/// Handles file changed events.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void FileSystemWatcher_Changed(object sender, FileSystemEventArgs e)
{
if (!lastFileChanged.Equals(e.Name))
{
string fileName = e.Name;
if (fileName.Contains(".xml"))
{
fileName = fileName.Replace(".xml", "");
if (fileName.Contains("Database"))
{
OnDatabaseChanged?.Invoke(this, new OnDatabaseChangedEventArgs(fileName, DateTime.Now));
}
}
lastFileChanged = e.Name;
}
else
{
lastFileChanged = string.Empty;
}
Console.WriteLine("Changed " + e.FullPath);
}
public void Add <T>(T t) where T : IDbEntity
{
AddType <T>();
Type type = typeof(T);
int id = ++IndexTracker[type];
t.EntityId = id;
Database[type].Add(t);
ApplyChanges();
OnDatabaseChanged?.Invoke(this);
OnEntityAdded?.Invoke(t);
}
/// <summary>
/// Saves a selection of items in its respective database.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="items"></param>
public void Save <T>(ICollection <T> items) where T : ICollectableObject
{
if (items.IsNull())
{
throw new ArgumentNullException("The parameter items cannot be null.");
}
DatabaseItemInfo <T> dbInfo = GetDatabaseItemInfo <T>();
var db = GetType().GetMethod("GetDatabase", BindingFlags.NonPublic | BindingFlags.Instance).MakeGenericMethod(dbInfo.DatabaseType).Invoke(this, null);
Type typeOfCollection = db.GetType().GetProperty(dbInfo.CollectionName).PropertyType;
object newItems = EnumerateCollection <T>(items);
if (typeOfCollection.BaseType == typeof(Array))
{
newItems = (newItems as ICollection <T>).ToArray();
}
else if (typeOfCollection.BaseType == typeof(Collection <T>))
{
newItems = (newItems as ICollection <T>).ToObservableCollection();
}
db.GetType().GetProperty(dbInfo.CollectionName).SetValue(db, newItems);
string path = GetDatabasePath(dbInfo.DatabaseType);
lock (lockObject)
{
var xml = db.Serialize();
try
{
try
{
if (!mutex.IsNull())
{
mutex.WaitOne();
}
xml.Save(path);
//Will fire the database changed event when the FileSystemWatcher is unavailable.
//This should happen only when using Xamarin.Forms as there is no native support for that class.
if (fileSystemWatcher.IsNull())
{
OnDatabaseChanged?.Invoke(this, new OnDatabaseChangedEventArgs(dbInfo.DatabaseType.Name, DateTime.Now));
}
}
catch
{
throw;
}
finally
{
if (!mutex.IsNull())
{
mutex.ReleaseMutex();
}
}
}
catch
{
throw;
}
finally
{
}
}
}
/// <summary>
/// Remove entity from Db
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="t"></param>
public void Remove <T>(T t) where T : IDbEntity
{
AddType <T>();
Type type = typeof(T);
Database[type].Remove(t);
// check entity references
foreach (KeyValuePair <Type, HashSet <IDbEntity> > kv in Database)
{
Type entityType = kv.Key;
EntityInfo infos = GetEntityInfo(entityType);
foreach (IDbEntity entity in kv.Value)
{
bool changed = false;
// single refs
foreach (SingleReferenceProperty referenceProperty in infos.SingleReferenceInjectors)
{
IDbReference dbReference = (IDbReference)referenceProperty.PropertyAccessor.GetValue(entity);
if (dbReference.ReferenceId == t.EntityId && dbReference.EntityType == type)
{
dbReference.ReferenceId = null;
dbReference.Entity = null;
changed = true;
}
}
// multiple refs
foreach (MultipleReferenceProperty referenceProperty in infos.MultipleReferenceInjectors)
{
IList dbReference = (IList)referenceProperty.PropertyAccessor.GetValue(entity);
if (dbReference == null)
{
continue;
}
for (int i = dbReference.Count - 1; i >= 0; i--)
{
IDbReference reference = (IDbReference)dbReference[i];
if (reference.ReferenceId == t.EntityId && reference.EntityType == type)
{
dbReference.RemoveAt(i);
changed = true;
}
}
}
if (changed)
{
OnEntityChanged?.Invoke(entity);
}
}
}
OnDatabaseChanged?.Invoke(this);
OnEntityRemoved?.Invoke(t);
}