an expression tree lambda may not contain a null propagating operator

Question

Question: The line price = co?.price ?? 0, in the following code gives me the above error. but if I remove ? from co.?

Answer 1

Jon Skeet's answer was right, in my case I was using DateTime for my Entity class. When I tried to use like

(a.DateProperty == null ? default : a.DateProperty.Date)

I had the error

Property 'System.DateTime Date' is not defined for type 'System.Nullable`1[System.DateTime]' (Parameter 'property')

So I needed to change DateTime? for my entity class and

(a.DateProperty == null ? default : a.DateProperty.Value.Date)