private static void InspectViewManager()
{
var finding = new DiagnosticFinding(
"Data binding to non-observable collection OR uage of non-observable collection together with CollectionViewSource causes higher memory footpint." +
"This is no real memory leak - the memory will be released after some 'Purge cylces' of the ViewManager. See http://referencesource.microsoft.com/PresentationFramework/Framework/MS/Internal/Data/ViewManager.cs.html",
"If you need to free the memory as soon as it is no longer needed by your application consider converting this collection into one which implements INotifyCollectionChanged (e.g. ObservableCollection<>) - even if the collection is immutable.");
var type = typeof(Binding).Module.GetType("MS.Internal.Data.ViewManager");
var viewManager = (IDictionary)type.GetProperty("Current", BindingFlags.Static | BindingFlags.NonPublic)
.GetValue(null);
if (viewManager == null)
{
return;
}
var inactiveViewTables = (IDictionary)type.GetField("_inactiveViewTables", BindingFlags.Instance | BindingFlags.NonPublic)
.GetValue(viewManager);
if (inactiveViewTables == null)
{
return;
}
if (inactiveViewTables.Count == 0)
{
return;
}
var entries = inactiveViewTables.OfType <DictionaryEntry>().ToList();
foreach (var entry in entries)
{
var viewTable = (IEnumerable)entry.Key;
var entryWithViewRecord = (DictionaryEntry)viewTable.OfType <object>().First();
var collectionView = (ICollectionView)entryWithViewRecord.Value.GetType()
.GetProperty("View", BindingFlags.Instance | BindingFlags.NonPublic)
.GetValue(entryWithViewRecord.Value);
var sourceCollection = collectionView.SourceCollection;
if (collectionView.IsEmpty)
{
continue;
}
finding.AddLocation("CollectionType={0}, Count={1}",
collectionView.SourceCollection.GetType().FullName,
collectionView.SourceCollection.OfType <object>().Count());
}
if (finding.Locations.Any())
{
Findings.Add(finding);
}
}
// resolution: RemoveValueChanged()
private static void InspectDPCustomTypeDescriptor()
{
var finding = new DiagnosticFinding(
"Observation of DependencyProperty using DependencyPropertyDescriptor.AddValueChanged() causes memory leak",
"Call DependencyPropertyDescriptor.RemoveValueChanged() to remove the event handler.");
var type = typeof(DependencyObject).Module.GetType("MS.Internal.ComponentModel.DPCustomTypeDescriptor");
var propertyMap = (IDictionary)type.GetField("_propertyMap", BindingFlags.Static | BindingFlags.NonPublic)
.GetValue(null);
if (propertyMap == null)
{
return;
}
foreach (DictionaryEntry entry in propertyMap)
{
var dependencyObjectPropertyDescriptor = entry.Value;
if (dependencyObjectPropertyDescriptor == null)
{
continue;
}
var trackers = GetTrackersFieldFromDependencyObjectPropertyDescriptor(dependencyObjectPropertyDescriptor);
if (trackers == null)
{
continue;
}
foreach (DictionaryEntry trackerEntry in trackers)
{
var tracker = trackerEntry.Value;
var changedHandler = (EventHandler)tracker.GetType()
.GetField("Changed", BindingFlags.Instance | BindingFlags.NonPublic)
.GetValue(tracker);
if (changedHandler == null)
{
continue;
}
finding.AddLocation("ObservedType={0}, ObservedProperty={1}, HandlerTarget={2}, HandlerName={3}",
tracker.GetType().GetField("_object", BindingFlags.Instance | BindingFlags.NonPublic)
.GetValue(tracker).GetType().FullName,
((DependencyProperty)tracker.GetType().GetField("_property", BindingFlags.Instance | BindingFlags.NonPublic).GetValue(tracker)).Name,
changedHandler.Target.GetType().FullName,
changedHandler.Method.Name);
}
}
if (finding.Locations.Any())
{
Findings.Add(finding);
}
}
// http://code.logos.com/blog/2008/10/detecting_bindings_that_should_be_onetime.html
// resolution: OneTime, INotifyPropertyChanged
private static void InspectReflectTypeDescriptionProvider()
{
var finding = new DiagnosticFinding(
"Data binding to non-observable property causes memory leak",
"Choose one of the following options:" + Environment.NewLine +
" a) convert to DependencyProperty" + Environment.NewLine +
" b) implement INotifyPropertyChanged in owning type" + Environment.NewLine +
" c) bind with BindingMode=OneTime");
var type = typeof(PropertyDescriptor).Module.GetType("System.ComponentModel.ReflectTypeDescriptionProvider");
var propertyCache = (Hashtable)type
.GetField("_propertyCache", BindingFlags.Static | BindingFlags.NonPublic)
.GetValue(null);
if (propertyCache == null)
{
return;
}
// try to make a copy of the hashtable as quickly as possible (this object can be accessed by other threads)
var entries = new DictionaryEntry[propertyCache.Count];
propertyCache.CopyTo(entries, 0);
var valueChangedHandlersFieldInfo = typeof(PropertyDescriptor)
.GetField("valueChangedHandlers", BindingFlags.Instance | BindingFlags.NonPublic);
foreach (var entry in entries)
{
var propertyDescriptors = (PropertyDescriptor[])entry.Value;
if (propertyDescriptors == null)
{
continue;
}
foreach (var propertyDescriptor in propertyDescriptors)
{
var valueChangedHandlers = (Hashtable)valueChangedHandlersFieldInfo.GetValue(propertyDescriptor);
if (valueChangedHandlers == null || valueChangedHandlers.Count == 0)
{
continue;
}
finding.AddLocation("ObservedType={0}, ObservedProperty={1}, HandlerCount={2}",
entry.Key, propertyDescriptor.Name, valueChangedHandlers.Count);
}
}
if (finding.Locations.Any())
{
Findings.Add(finding);
}
}
// resolution: RemoveValueChanged()
private static void InspectDPCustomTypeDescriptor()
{
var finding = new DiagnosticFinding(
"Observation of DependencyProperty using DependencyPropertyDescriptor.AddValueChanged() causes memory leak",
"Call DependencyPropertyDescriptor.RemoveValueChanged() to remove the event handler.");
var type = typeof(DependencyObject).Module.GetType("MS.Internal.ComponentModel.DPCustomTypeDescriptor");
var propertyMap = (IDictionary)type.GetField("_propertyMap", BindingFlags.Static | BindingFlags.NonPublic)
.GetValue(null);
if (propertyMap == null)
{
return;
}
foreach (DictionaryEntry entry in propertyMap)
{
var dependencyObjectPropertyDescriptor = entry.Value;
if (dependencyObjectPropertyDescriptor == null)
{
continue;
}
var trackers = GetTrackersFieldFromDependencyObjectPropertyDescriptor(dependencyObjectPropertyDescriptor);
if (trackers == null)
{
continue;
}
foreach (DictionaryEntry trackerEntry in trackers)
{
var tracker = trackerEntry.Value;
var changedHandler = (EventHandler)tracker.GetType()
.GetField("Changed", BindingFlags.Instance | BindingFlags.NonPublic)
.GetValue(tracker);
if (changedHandler == null)
{
continue;
}
finding.AddLocation("ObservedType={0}, ObservedProperty={1}, HandlerTarget={2}, HandlerName={3}",
tracker.GetType().GetField("_object", BindingFlags.Instance | BindingFlags.NonPublic)
.GetValue(tracker).GetType().FullName,
((DependencyProperty)tracker.GetType().GetField("_property", BindingFlags.Instance | BindingFlags.NonPublic).GetValue(tracker)).Name,
changedHandler.Target.GetType().FullName,
changedHandler.Method.Name);
}
}
if (finding.Locations.Any())
{
Findings.Add(finding);
}
}
private static void InspectViewManager()
{
var finding = new DiagnosticFinding(
"Data binding to non-observable collection OR uage of non-observable collection together with CollectionViewSource causes higher memory footpint."+
"This is no real memory leak - the memory will be released after some 'Purge cylces' of the ViewManager. See http://referencesource.microsoft.com/PresentationFramework/Framework/MS/Internal/Data/ViewManager.cs.html",
"If you need to free the memory as soon as it is no longer needed by your application consider converting this collection into one which implements INotifyCollectionChanged (e.g. ObservableCollection<>) - even if the collection is immutable.");
var type = typeof(Binding).Module.GetType("MS.Internal.Data.ViewManager");
var viewManager = (IDictionary)type.GetProperty("Current", BindingFlags.Static | BindingFlags.NonPublic)
.GetValue(null);
if (viewManager == null)
{
return;
}
var inactiveViewTables = (IDictionary)type.GetField("_inactiveViewTables", BindingFlags.Instance | BindingFlags.NonPublic)
.GetValue(viewManager);
if (inactiveViewTables == null)
{
return;
}
if (inactiveViewTables.Count == 0)
{
return;
}
var entries = inactiveViewTables.OfType<DictionaryEntry>().ToList();
foreach (var entry in entries)
{
var viewTable = (IEnumerable)entry.Key;
var entryWithViewRecord = (DictionaryEntry)viewTable.OfType<object>().First();
var collectionView = (ICollectionView)entryWithViewRecord.Value.GetType()
.GetProperty("View", BindingFlags.Instance | BindingFlags.NonPublic)
.GetValue(entryWithViewRecord.Value);
var sourceCollection = collectionView.SourceCollection;
if (collectionView.IsEmpty)
{
continue;
}
finding.AddLocation("CollectionType={0}, Count={1}",
collectionView.SourceCollection.GetType().FullName,
collectionView.SourceCollection.OfType<object>().Count());
}
if (finding.Locations.Any())
{
Findings.Add(finding);
}
}
// http://code.logos.com/blog/2008/10/detecting_bindings_that_should_be_onetime.html
// resolution: OneTime, INotifyPropertyChanged
private static void InspectReflectTypeDescriptionProvider()
{
var finding = new DiagnosticFinding(
"Data binding to non-observable property causes memory leak",
"Choose one of the following options:" + Environment.NewLine +
" a) convert to DependencyProperty" + Environment.NewLine +
" b) implement INotifyPropertyChanged in owning type" + Environment.NewLine +
" c) bind with BindingMode=OneTime");
var type = typeof(PropertyDescriptor).Module.GetType("System.ComponentModel.ReflectTypeDescriptionProvider");
var propertyCache = (Hashtable)type
.GetField("_propertyCache", BindingFlags.Static | BindingFlags.NonPublic)
.GetValue(null);
if (propertyCache == null)
{
return;
}
// try to make a copy of the hashtable as quickly as possible (this object can be accessed by other threads)
var entries = new DictionaryEntry[propertyCache.Count];
propertyCache.CopyTo(entries, 0);
var valueChangedHandlersFieldInfo = typeof(PropertyDescriptor)
.GetField("valueChangedHandlers", BindingFlags.Instance | BindingFlags.NonPublic);
foreach (var entry in entries)
{
var propertyDescriptors = (PropertyDescriptor[])entry.Value;
if (propertyDescriptors == null)
{
continue;
}
foreach (var propertyDescriptor in propertyDescriptors)
{
var valueChangedHandlers = (Hashtable)valueChangedHandlersFieldInfo.GetValue(propertyDescriptor);
if (valueChangedHandlers == null || valueChangedHandlers.Count == 0)
{
continue;
}
finding.AddLocation("ObservedType={0}, ObservedProperty={1}, HandlerCount={2}",
entry.Key, propertyDescriptor.Name, valueChangedHandlers.Count);
}
}
if (finding.Locations.Any())
{
Findings.Add(finding);
}
}
