private void deletePlaneBtn_Click(object sender, EventArgs e)
        {
            showAllConveyance showAllConveyanceObj = new showAllConveyance("Plane", "deleteShow");

            showAllConveyanceObj.ShowDialog();
        }
        private void showAllPlanesBtn_Click(object sender, EventArgs e)
        {
            showAllConveyance showAllConveyanceObj = new showAllConveyance("Plane", "show");

            showAllConveyanceObj.Show();
        }
        private void updateBusBtn_Click(object sender, EventArgs e)
        {
            showAllConveyance showAllConveyanceObj = new showAllConveyance("Bus", "updateShow");

            showAllConveyanceObj.ShowDialog();
        }
        private void showAllTrainBtn_Click(object sender, EventArgs e)
        {
            showAllConveyance showAllConveyanceObj = new showAllConveyance("Train", "show");

            showAllConveyanceObj.Show();
        }