數字轉國字 - 不定長度

Public Class Form1
    Dim i, str1
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim s1 = "1234567"
        Dim s2 = "拾佰仟萬拾佰仟億"
        str1 = Mid(s1, Len(s1), 1)
        For i = Len(s1) - 1 To 1 Step -1
            str1 = Mid(s1, i, 1) & Mid(s2, Len(s1) - 1 + 1 - i, 1) & str1
        Next
        MsgBox(str1)
    End Sub
End Class