If the members are in different
classes/structs
and are marked as
private.
You will need to use the default level of internal if the
classes/structs
are
within the same assembly.
If they are in
different assemblies, then the members will need to be marked as
public to be accessible.
In your code, just check the method
DisplayGroupTree
which you're trying to access is
not private.
Please also note that you can span a single
class/struct
across multiple source files using the
partial keyword.
Look at following links with more information:
http://msdn.microsoft.com/en-us/library/ms173121(VS.80).aspx[
^]
http://msdn.microsoft.com/en-us/library/wa80x488(VS.80).aspx[
^]