Private Sub Timer3_Tick(sender As System.Object, e As System.EventArgs) Handles Timer3.Tick
        Dim DayofNow As Date
        Dim DayofSchedule As Date
        If CheckBox2.Checked = True Then
            DayofNow = Now.Date
            DayofSchedule = cmb_mouth.Text.ToString + "/" + cmb_day.Text.ToString + "/" +  Now.Year.ToString
            If DayofNow >= DayofSchedule Then
                TextBox2.BackColor = Color.Red
                TextBox2.Text = "行程日期已到"
            Else
                TextBox2.BackColor = Color.AliceBlue
                TextBox2.Text = "行程日期未到"
            End If
        End If
End Sub