多位数乘多位数并输入到文档

Private Sub Command1_Click()
Dim c As Byte
Dim a() As Byte
Dim b As String
Dim changdu As Integer, i As Long
changdu = Len(Text1.Text)
ReDim a(changdu)

For i = 1 To changdu
b = Mid(Me.Text1.Text, i, 1)
a(i) = Int(Val(b))
Next i

b = Me.Text2.Text
c = Int(Val(b))
Dim rm As Byte
Dim r() As Byte
ReDim r(changdu)


For i = changdu To 1 Step -1
rm = a(i) * c + d
r(i) = rm Mod 10
d = rm \ 10
Next i


If d <> 0 Then
Print d;
End If

For i = 1 To changdu
Print r(i);
Next i


Open "D:\VB\TEXT.txt" For Output As #1

If d <> 0 Then
Print #1, d;
End If

For i = 1 To changdu
Print #1, r(i);
Next i
Close #1



End Sub