sub encode_url$(s$, exclusions$, spaceplus)
    local res$, i, ch$
	
    for i=1 to len(s$)
        ch$ = mid$(s$, i, 1)
        if ch$ = " " and spaceplus then
            ch$ = "+"
        elsif not instr(esclusions$, ch$) and (ch$ < "0" or (ch$ > "9" and ch$ < "A") or (ch$ > "Z" and ch$ < "a") or  ch$ > "z") then
            res$ = res$ + "%"
            ch$ = upper$(hex$(asc(ch$)))
        end if
        res$ = res$ + ch$
    next i
    return res$
end sub

print encode_url$("http://foo bar/")