AFAICT, it's not only "internal representation". .NET strings are defined as a sequence of UTF-16 units, including the definition of the Char type representing

AFAICT, it's not only "internal representation". .NET strings are defined as a sequence of UTF-16 units, including the definition of the Char type representing a single UTF-16 code unit. I can't imagine how such a change could be implemented (other than changing the internal representation but converting on all accesses which would be nonsense, I think).