>>
>>Thank you again. In the meantime, I discovered several VFP user functions. I will test them (including yours) and see which one is the fastest and complete.
>
>For completeness sake, the lines checking for the necessity of encoding should be changed to
>
>

>		IF ASC(m.CharAt) >= 128 OR m.CharAt $ ":/?#[]@!$&'()*+,;=%" OR m.CharAt <= " "
>			m.CharAt = "%" + STRCONV(m.CharAt,15)
>		ENDIF
>

Right, because "not greater than space" may not cover all of those punctuation characters, depending on the current collation sequence. I think I've seen one where

?" ">"!"

returns .t.