DIM SHARED i, j, a$, Stak$[41]

CLS

a$ = "1,22,333,4444,55555,666666,7777777,88888888,999999999,"

i = Parse(a$, ",")

FOR j = 1 TO i
  PRINT Stak$[j]
NEXT j

FUNCTION Parse (Lyne$, Delim$)
  LOCAL Element
  LOCAL A
  LOCAL Tmp
  LOCAL Lin$

  FOR Tmp = 1 TO 40
    Stak$[Tmp] = ""
  NEXT Tmp

  Lin$ = Lyne$ : A = 1 : Element = 1

  WHILE A > 0
    A = INSTR(Lin$, Delim$)
    IF A > 0 THEN
      Stak$[Element] = MID$(Lin$, 1, A - 1)
      Lin$ = MID$(Lin$, A + 1, LEN(Lyne$))
      IF LEN(Stak$[Element]) = 0 THEN DECR Element
      INCR Element
    END IF
  WEND
  Stak$[Element] = Lin$
  IF LEN(Stak$[Element]) = 0 THEN DECR Element
  FUNCTION = Element
END FUNCTION

Result:

1
22
333
4444
55555
666666
7777777
88888888
999999999