用VB设计一个倒计时器，能够设置倒计时的时间，并进行倒计时

Option Explicit
Dim SetTime As Integer

Private Sub Command1_Click()
Timer1.Interval = 1000
SetTime = CInt(Text1)
Timer1.Enabled = True

End Sub

Private Sub Timer1_Timer()
SetTime = SetTime - 1
If SetTime = 0 Then
MsgBox "时间到"
End If
End Sub

text1里面输入倒计时时间（秒），command1开始倒计时