Catel 5.0

This guide describes how to update your code to be fully compatible with Catel 5.0.


Catel v5 contains a lot of breaking changes, not all of them cause compiler errors but change core behavior. It's important to check out the guide below before updating to Catel v5.


This guide assumes that you are coming from Catel 4.5. If not, please read that guide first.

Encountered issues while upgrading to this version? Add them here to help out others!

Platform support changes

Added support for the following platforms:

  • .NET 4.7

Removed support for the following platforms:

  • .NET 4.0
  • Silverlight 5
  • Windows Phone 8.0 (Silverlight)
  • Windows Phone 8.1 (Silverlight)
  • Windows Phone 8.1 (Runtime)
  • Windows 8.1 (Runtime)

Moved extensions

The following extensions have been moved to a new repository:

Removed extensions

The following extensions have been removed:

  • Catel.Extensions.CSLA
  • Catel.Extensions.Data
  • Catel.Extensions.Interception
  • Catel.Extensions.MVC4
  • Catel.Extensions.MVC5
  • Catel.Extensions.Prism4
  • Catel.Extensions.Wcf.Server



Note that if you are using Catel.Fody, you must update to at least 2.17 to support Catel 5.



CommandLineHelper has been removed. Use Orc.CommandLine instead.


DynamicEventListener has been removed. Use WeakEventListener instead.


The ModelBase has been greatly simplified to decrease the memory print and improve performance. The class is split up into separate classes:

  • ModelBase => takes care of basic serialization and property bag registrations
  • ValidatableModelBase => adds validation
  • ChildAwareModelBase => contains the child event subscriptions logic (which is very costly)
  • SavableModelBase => adds Save and Load methods
  • ComparableModelBase => contains the equality comparer members. This means the ModelBase itself does no longer support equality checks based on the property values


XAML namespace changes

The xaml namespace has changed from to


CountCollapsedConverter has been removed. Use CollectionToVisibilityConverter instead.


EffectsHelper has been removed. No replacement is available.


The ViewModelBase has been simplified. It now derives from ValidatingModelBase (so still supports validation). The following features / members have been removed:

  • HasDirtyModels has been removed
  • Validation summaries (use the ValidationContext instead)


VisualTargetPresentationSource has been removed. No replacement is available.