For my blazor library which is a modification of this awesome library I have to convert an ExpandoObject into a Dictionary<string, object> since ExpandoObjects aren't serialized properly in the newest preview versions of dotnet-core. See my question related to this for more details.

My current approach goes as follows:

Dictionary<string, object> ConvertDynamicToDictonary(IDictionary<string, object> value) { return value.ToDictionary( p => p.Key, p => { // if it's another IDict (might be a ExpandoObject or could also be an actual Dict containing ExpandoObjects) just go through it recursively if (p.Value is IDictionary<string, object> dict) { return ConvertDynamicToDictonary(dict); } // if it's an IEnumerable, it might have ExpandoObjects inside, so check for that if (p.Value is IEnumerable<object> list) { if (list.Any(o => o is ExpandoObject)) { // if it does contain ExpandoObjects, take all of those and also go through them recursively return list .Where(o => o is ExpandoObject) .Select(o => ConvertDynamicToDictonary((ExpandoObject)o)); } } // neither an IDict nor an IEnumerable -> it's probably fine to just return the value it has return p.Value; } ); } 

This works fine but I'm not sure about the IEnumerable part. If I omit the list.Any check it still works fine. New version (only write the IEnumerable part changed):

// if it's an IEnumerable, it might have ExpandoObjects inside, so check for that if (p.Value is IEnumerable<object> list) { // take all ExpandoObjects and go through them recursively return list .Where(o => o is ExpandoObject) .Select(o => ConvertDynamicToDictonary((ExpandoObject)o)); } 

I have also tried using IEnumerable<ExpandoObject> instead of just IEnumerable<object> to see if that would work and maybe be cleaner and I can confirm that that does not work (throws error).

What I would like to know now is, if it's a good idea to omit the Any check and which option is more performant (and why) and/or cleaner.
Also please mention every small thing that bugs you, I always want to make it as perfect as possible :)

I first wanted to post this on StackOverflow but I think it fits better on here - correct me if I'm wrong.