coding calculator

CODING UNTUK (SAMA DENGAN ) = DO CASE
    CASE C = "tambah"
    TOTAL = VAL(B) + VAL(A)
    thisform.text1.Value = STR (TOTAL)
    A = ""


    CASE C = "kurang"
    TOTAL = VAL(B) - VAL(A)
    thisform.text1.Value = STR(total)
    A = ""
    CASE C = "kali"
    TOTAL = VAL(B) * VAL(A)
    thisform.text1.Value = STR(total)
    A = ""
    CASE C = "bagi"
    IF A = "0"
        thisform.text1.Value = "EROR: tak bisa"
        A = ""
    ELSE
    TOTAL = VAL(B) /VAL(A)
    thisform.text1.Value = STR(total)
    A = ""
    ENDIF
ENDCASE
 CODING UNTUK ANGAKA 1 SAMPAI DENGAN 9 =
thisform.text1.Value="1"
A = A + thisform.text1.Value
thisform.text1.Value = A
CODING UNTUK PERKALIAN X =
C = "kali"
B = thisform.text1.Value
A = ""
CODING UNTUK PENGURANGAN - =
C = "kurang"
B = thisform.text1.Value
A = ""
CODING UNTUK PEMBAGIAN / =
C = "bagi"
B = thisform.text1.Value
A = ""
CODING UNTUK PENAMBAHAN + =
C = "bagi"
B = thisform.text1.Value
A = ""
CODING UNTUK KELUAR/ EXIT =
THISFORM.RELEASE