Warning when using Hexadecimal values in VBA.

[xavier.batlle]

If I print some hexadecimal values, this is the result:

? &HF
 15
? &HFF
 255
? &HFFF
 4095
? &HFFFF
-1
? &HFFFFF
 1048575
? &HFFFFFF
 16777215
? &HFFFF = &HFFFFFFFF
True
?  &HFFFF , &HFFFFFFFF
-1            -1

All hex decimal values from &H0000 to &HFFFF are considered signed integer type so the &HFFFF value is -1. Greater values than &HFFFF are considered long values and work properly from values lower than &H7FFFFFFF.
So If you have to work with hexadecimal numbers, they must be explicity converted to avoid these issues.

 

[AHeyne]

Did you ever read about data type characters?

You have the possibility to use them to give your constant values a specific datatype, so that the automatism of VBA can be overwritten:

?&HFFFF, TypeName(&HFFFF)
-1            Integer
?&HFFFF&, TypeName(&HFFFF&)
 65535        Long