用MMControl播放avi文件的问题？

我的代码如下：
Private Sub Play1_Click()
    MMControl1.hWndDisplay = Picture1.hWnd
    MMControl1.filename = "c:\temp.avi"
    MMControl1.DeviceType = "AVIVIDEO"
    Picture1.AutoRedraw = True
    MMControl1.Command = "OPEN"
    MMControl1.To = 1
    MMControl1.Command = "SEEK"
    MMControl1.Command = "PLAY"
End Sub可是点击之后，没有任何反应，也没有报错？请指教，先行谢过！！