public static TriggerPath Factory(Expression path)
{
var body = (path as LambdaExpression)?.Body;
var e = body;
TriggerPath triggerPath = null;
while (e != null)
{
var name = "";
if (e.NodeType == ExpressionType.Convert)
{
e = (e as UnaryExpression)?.Operand;
}
else
{
switch (e)
{
case MemberExpression m:
name = m.Member.Name;
e = m.Expression;
break;
case MethodCallExpression mc:
name = mc.Method.Name;
e = mc.Arguments[0];
break;
default:
throw new ArgumentException("Error parsing expression : " + path.ToString());
}
}
if (e is { NodeType : ExpressionType.Parameter })
public static TriggerPath Factory(Expression path)
{
var body = (path as LambdaExpression)?.Body;
if (body?.NodeType == ExpressionType.Convert)
{
body = (body as UnaryExpression)?.Operand;
}
var e = body;
TriggerPath triggerPath = null;
while (e != null)
{
var name = "";
if (e is MemberExpression m)
{
name = m.Member.Name;
e = m.Expression;
}
else if (e is MethodCallExpression mc)
{
name = mc.Method.Name;
e = mc.Arguments[0];
}
else
{
throw new ArgumentException("Error parsing expression : " + path.ToString());
}
if (e.NodeType == ExpressionType.Parameter)
{
e = null;
triggerPath = Factory(triggerPath, name);
}
else
{
triggerPath = Factory(triggerPath, name);
}
}
return(triggerPath);
}
public static TriggerPath Factory(params string[] path)
{
var stack = new Stack <string>();
foreach (var subPath in path)
{
var sub = subPath.Split('.');
foreach (var propertyName in sub)
{
stack.Push(propertyName);
}
}
TriggerPath triggerPath = null;
while (stack.TryPop(out var propertyName))
{
triggerPath = Factory(triggerPath, propertyName);
}
return(triggerPath ?? new TriggerPathNull());
}
protected TriggerOnEntry(TriggerPath path, PropertyChangedEventHandler handler)
{
Path = path;
Handler = handler;
}
public TriggerOnEntryNotifier(PropertyChangedEventHandler handler, INotifierPropertyEntry entry, TriggerPath path)
: base(path, handler)
{
entry.PropertyChanged += Handler;
_onDispose = () => entry.PropertyChanged -= Handler;
if (Path == null)
{
return;
}
void NextHandler(object sender, PropertyChangedEventArgs arg)
{
_next?.Dispose();
if (arg is NotifierPropertyChangedEventArgs notifierArg)
{
_next = notifierArg.NewValue != null?Subscribe(notifierArg.NewValue) : null;
}
}
entry.RegisterValue += NextHandler;
_onDispose += () => entry.RegisterValue -= NextHandler;
_onDispose += () => _next?.Dispose();
if (!entry.IsSet)
{
entry.Update();
}
var value = entry.GetValue();
NextHandler(null, new NotifierPropertyChangedEventArgs(entry, null, value));
}
private static TriggerPath Factory(TriggerPath next, string propertyName)
{
return(next == null ? new TriggerPath(propertyName) : new TriggerPathNext(next, propertyName));
}
internal TriggerPathNext(TriggerPath next, string propertyName) : base(propertyName)
{
Next = next;
}
public TriggerOnAttribute(params string[] path)
{
Path = TriggerPath.Factory(path);
}
public TriggerOnEntryCollection(PropertyChangedEventHandler handler, INotifyCollectionChanged collection, TriggerPath path)
: base(path, handler)
{
_collection = collection;
if (path != null)
{
_collection.CollectionChanged += OnCollectionChanged_Subscribe;
OnCollectionChanged_Subscribe(collection, new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, (IList)_collection));
}
_collection.CollectionChanged += OnCollectionChanged_Handler;
}
