There was some talk of this being implemented, but I can no longer find the forum thread or anything else that I was reading last time I looked into this.
I know how to pass parameters to my controls that I use in a Radzen Dialog but are able to pass in call backs yet?
As I say, I do remember reading in here once over that your team was thinking of adding this feature, may have been on the road-map document or somewhere.
I'm sure I can speak for a lot of people when I say that it would be a welcome addition to the DialogService/Component.
This is actually a limitation of .NET / C# - you can add a method to a Dictionary (which is what the dialog parameters argument is). You can try this instead: