How to use mousewheel and timer to adjust the value automatically?

using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace WinMouse1
{
    /// <summary>
    /// Change the transparency of the form using the mousewheel
    /// </summary>
    public partial class Form2 : Form
    {
        [DllImport("user32.dll", EntryPoint = "GetWindowLongA", SetLastError = true)]
        private static extern int GetWindowLong(IntPtr hwnd, int nIndex);

        [DllImport("user32.dll", EntryPoint = "SetWindowLongA", SetLastError = true)]
        private static extern int SetWindowLong(IntPtr hwnd, int nIndex, int dwNewLong);

        [DllImport("user32.dll")]
        static extern bool SetLayeredWindowAttributes(IntPtr hwnd, uint crKey, byte bAlpha, uint dwFlags);

        public const int GWL_EXSTYLE = -20;
        public const int WS_EX_LAYERED = 0x80000;
        public const int LWA_ALPHA = 0x2;

        Timer myTimer = new Timer();
        int mousedeltaval = 0;
        int alpha = 255;
        bool running;

        public Form2()
        {
            InitializeComponent();
            myTimer.Interval = 100;
            myTimer.Tick += MyTimerTick;
            this.MouseWheel += MyMouseWheel;
        }

        private void MyMouseWheel(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            if (running)
            {
                running = false;
                myTimer.Stop();
                System.Threading.Thread.Sleep(50);
                return;
            }

            if (e.Delta < 0)
            {
                mousedeltaval = -10;
            }
            else
            {
                mousedeltaval = 10;
            }

            running = true;
            System.Threading.Thread.Sleep(50);
            myTimer.Start();
        }

        private void MyTimerTick(Object myObject, EventArgs myEventArgs)
        {
            alpha += mousedeltaval;

            if (alpha > -1 && alpha < 255)
            {
                SetWindowLong(Handle, GWL_EXSTYLE, GetWindowLong(Handle, GWL_EXSTYLE) | WS_EX_LAYERED);
                SetLayeredWindowAttributes(Handle, 0, (byte)alpha, LWA_ALPHA);
                return;
            }

            if (alpha < 0)
            {
                alpha = 0;
            }
            else
            {
                alpha = 255;
            }

            running = false;
            myTimer.Stop();
            Debug.Print("alpha = " + alpha);
        }
    }
}