Merge branch 'master' of https://github.com/icsharpcode/WpfDesigner

Author: jogibear9988

README.md

@@ -1,5 +1,5 @@
 # WpfDesigner
-The WPF Designer from SharpDevelop
+The WPF Designer from SharpDevelop, available via [NuGet](https://www.nuget.org/packages/ICSharpCode.WpfDesigner/)
 
 ## Overview
 
@@ -14,18 +14,14 @@ Branch | Status
 
 ## System Requirements
 
-.NET 4.5 or Net Core 3.0
+.NET 4.5, or .NET Core 5.0 as well as .NET 6.0
 
 ## Libraries and Integrated Tools
 
 Only the sample app has dependencies:
 * [Avalon Dock](http://avalondock.codeplex.com/)
 * [Avalon Edit](https://github.com/icsharpcode/AvalonEdit)
 
-## Download
-
-[NuGet](https://www.nuget.org/packages/ICSharpCode.WpfDesigner/)
-
 ## Sample App
 ![Sample App](/screenshot.png?raw=true "Sample App")
 

WpfDesign.Designer/Project/PropertyGrid/Editors/FlatCollectionEditor.xaml.cs

@@ -116,7 +116,20 @@ public void LoadItemsCombobox()
 
 		private IEnumerable<Type> GetInheritedClasses(Type type)
 		{
-			return AppDomain.CurrentDomain.GetAssemblies().Where(x => !x.IsDynamic).SelectMany(x => x.GetTypes().Where(y => y.IsClass && !y.IsAbstract && y.IsSubclassOf(type)));
+			return AppDomain.CurrentDomain.GetAssemblies().Where(x => !x.IsDynamic).SelectMany(x => GetLoadableTypes(x).Where(y => y.IsClass && !y.IsAbstract && y.IsSubclassOf(type)));
+		}
+
+		private IEnumerable<Type> GetLoadableTypes(Assembly assembly)
+		{
+			if (assembly == null) throw new ArgumentNullException("assembly");
+			try
+			{
+				return assembly.GetTypes();
+			}
+			catch (ReflectionTypeLoadException e)
+			{
+				return e.Types.Where(t => t != null);
+			}
 		}
 
 		private void OnAddItemClicked(object sender, RoutedEventArgs e)