VB编程：GetSetting控制软件试用期

Private Sub Form_Load()
    Dim ss As Date
    Dim dd As Integer

    If GetSetting(appname:="this", section:="user", Key:="time") = "" Then
        MsgBox "尊敬的用户：您好！您还没有注册软件，从现在开始，你的试用期为30天！"
        SaveSetting appname:="this", section:="user", Key:="time", setting:=Date
    Else
        ss = GetSetting(appname:="this", section:="user", Key:="time")
        dd = Date - ss
        If dd > 30 Then
            MsgBox "对不起，您的试用期已到！"
            Unload Me
        Else
            MsgBox "您现在还没有注册软件，试用期还有" & 30 - dd & "天！"
        End If
    
    End If
End Sub