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:

Removed support for the following platforms:

Moved extensions

The following extensions have been moved to a new repository:

Removed extensions

The following extensions have been removed:


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:


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:


VisualTargetPresentationSource has been removed. No replacement is available.


We would like to thank the following contributors:

Want to contribute to the documentation? We have a guide for that!


Have a question about Catel? Use StackOverflow with the Catel tag!