Ok thank you but another step now hehe
In the fild i have this formula
(toNumber ("0"+Cstr({tablename.fieldname})))
The tablename.fieldname is a number like 1234
I've put cstr command because i need to put a 0 before him so he can be seen on print like 01234
I dont know why the Cstr command transform a field number in a string field but with toNumber i can transform back to number
The problem is that now the field reconverted to number suppress the initial 0 that i've put with the Cstr command
There's a way to see that 0?
Thank you by now