Working with "nul" value in MSPositional

[Anonymous]

Hello,

I'm receiving a positional file with the values below:

When I read the file, the records that I mapped with "Date" format, is receiving null correctly. However, when I try to get this same null value with "String" mapped format, I can't, because the field appears as an empty string. Is there a way that I can get all data type as null?

Thank you!