关于vb.net中未处理COMException

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    Private Sub StopLive1(ByVal Cam_handle As Object)

        If Live1 = False Then
            '*************************************************************
            '停止
            Pylon.DeviceExecuteCommandFeature(Cam_handle, "AcquisitionStop")


            ' ... Switch off the events.


            Pylon.DeviceFeatureFromString(Cam_handle, "EventSelector", "ExposureEnd")
            Pylon.DeviceFeatureFromString(Cam_handle, "EventNotification", "Off")
            Pylon.StreamGrabberCancelGrab(hStreamGrabber)

'上面三句话偶尔出现未处理COMException错误，有时是好的

            Do

                isReady = Pylon.StreamGrabberRetrieveResult(hStreamGrabber, GrabResult)
            Loop While isReady