C#

using System.IO.Ports;<br />
...<br />
 private SerialPort port = null;<br />
...<br />
  port = new SerialPort("COM15", 115200, Parity.None, 8, StopBits.One);<br />
  port.Open();<br />
  bool stop=false;<br />
  while(!stop){<br />
   while (port.BytesToRead>0)<br />
   {<br />
    int c=port.ReadByte();  // I've tried the other read-methods, too<br />
   }<br />
  }<br />
...

<br />
private void btn_Path_Click(object sender, EventArgs e)<br />
{<br />
Bitmap path = new Bitmap(@"C:\Engg\Siren.JPG");<br />
Graphics graph = Graphics.FromImage( this.imgViewer.Image );<br />
graph.DrawImage(path, 0, 0);<br />
<br />
graph.Dispose();<br />
}<br />

<br />
// this is in the form controlling the hook.<br />
public frmControl()<br />
        {<br />
            kHook.KeyPressEvent += new KeyEventHandler(kHook_KeyPress);<br />
        }<br />
<br />
        void kHook_KeyPress(object sender, KeyEventArgs e)<br />
        {<br />
            string keyPressed = ((Keys)e.KeyValue).ToString();<br />
            MessageBox.Show(keyPressed);<br />
        }<br />
<br />
// the actual keyboard hook class<br />
class KeyboardHook<br />
    {<br />
        public bool isHookActive = false;<br />
        private const int WH_KEYBOARD_LL = 13;<br />
        private const int WM_KEYDOWN = 0x0100;<br />
        private static LowLevelKeyboardProc _proc = HookCallback;<br />
        private static IntPtr _hookID = IntPtr.Zero;<br />
<br />
        public KeyboardHook()<br />
        {<br />
        }<br />
<br />
        public void StartKeyboardHook()<br />
        {<br />
            _hookID = SetHook(_proc);<br />
            isHookActive = true;<br />
        }<br />
<br />
        public void StopKeyboardHook()<br />
        {<br />
            UnhookWindowsHookEx(_hookID);<br />
            isHookActive = false;<br />
        }<br />
<br />
        private static IntPtr SetHook(LowLevelKeyboardProc proc)<br />
        {<br />
            using (Process curProcess = Process.GetCurrentProcess())<br />
            using (ProcessModule curModule = curProcess.MainModule)<br />
            {<br />
                return SetWindowsHookEx(WH_KEYBOARD_LL, proc,<br />
                    GetModuleHandle(curModule.ModuleName), 0);<br />
            }<br />
        }<br />
<br />
        private delegate IntPtr LowLevelKeyboardProc(<br />
            int nCode, IntPtr wParam, IntPtr lParam);<br />
<br />
        public static IntPtr HookCallback(<br />
            int nCode, IntPtr wParam, IntPtr lParam)<br />
        {<br />
            if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)<br />
            {<br />
                int vkCode = Marshal.ReadInt32(lParam);<br />
                //Console.WriteLine((Keys)vkCode);<br />
                //MessageBox.Show(((Keys)vkCode).ToString());<br />
                KHookArgs kh = new KHookArgs(vkCode);<br />
                KeyPressEvent(kh);<br />
            }<br />
            return CallNextHookEx(_hookID, nCode, wParam, lParam);<br />
        }<br />
<br />
        public delegate void KeyPressHandler(KHookArgs kh);<br />
<br />
        public event KeyEventHandler KeyPressEvent;<br />
<br />
        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]<br />
        private static extern IntPtr SetWindowsHookEx(int idHook,<br />
            LowLevelKeyboardProc lpfn, IntPtr hMod, uint dwThreadId);<br />
<br />
        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]<br />
        [return: MarshalAs(UnmanagedType.Bool)]<br />
        private static extern bool UnhookWindowsHookEx(IntPtr hhk);<br />
<br />
        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]<br />
        private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode,<br />
            IntPtr wParam, IntPtr lParam);<br />
<br />
        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]<br />
        private static extern IntPtr GetModuleHandle(string lpModuleName);<br />
    }<br />
<br />
    // custom attributes<br />
    public class KHookArgs : EventArgs<br />
    {<br />
        private string keyValue;<br />
<br />
        public KHookArgs(int k)<br />
        {<br />
            keyValue = ((Keys)k).ToString();<br />
        }<br />
<br />
        public string ReturnKey()<br />
        {<br />
            return keyValue;<br />
        }<br />
    }<br />