Question

I know how to modify cursor position from examples on MSDN.

My question is how to check position of mouse while mouse moves and then print X and Y position to representing labels?

EDIT: Lets say I want to track my mouse position from my entire screen.

EDIT 2: My app will be in the back ground/minimized.

I’m already using Mouse Hooks:

namespace Program
{
    public partial class MouseHook
    {
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
        private static extern void mouse_event(int dwFlags, int dx, int dy, int dwData, IntPtr dwExtraInfo);

        private const int MOUSEEVENTF_LEFTDOWN = 0x02;
        private const int MOUSEEVENTF_LEFTUP = 0x04;
        private const int MOUSEEVENTF_RIGHTDOWN = 0x08;
        private const int MOUSEEVENTF_RIGHTUP = 0x10;

        public void DoMouseClick()
        {
            int X = Cursor.Position.X;
            int Y = Cursor.Position.Y;

            IntPtr newP = new IntPtr(Convert.ToInt64("0", 16));
            mouse_event(MOUSEEVENTF_LEFTDOWN | MOUSEEVENTF_LEFTUP, X, Y, 0, newP);
        }
    }
}

Answer 1

Here is the msdn documentation on system level mouse event handling calls (low level mouse proc).

Here is an example of using low level mouse procs to change the scroll event.

In the answer in the second link use WM_MOUSEMOVE from here instead of WM_MOUSEWHEEL.

One thing to note: for this program to continue to capture mouse events when the mouse is over a program with elevated privileges, this program will have to be launch with elevated privileges.

Code (not tested):

using System;

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

namespace CatchMouseMove
{
    class InterceptMouse
    {
        const int INPUT_MOUSE = 0;
        const int MOUSEEVENTF_WHEEL = 0x0800;
        const int WH_MOUSE_LL = 14; 


        private static LowLevelMouseProc _proc = HookCallback;
        private static IntPtr _hookID = IntPtr.Zero;

        public static void Main()
        {
            _hookID = SetHook(_proc);

            if (_hookID == null)
            {
                MessageBox.Show("SetWindowsHookEx Failed");
                return;
            }
            Application.Run();
            UnhookWindowsHookEx(_hookID);
        }

        private static IntPtr SetHook(LowLevelMouseProc proc)
        {
            using (Process curProcess = Process.GetCurrentProcess())
            using (ProcessModule curModule = curProcess.MainModule)
            {
                return SetWindowsHookEx(WH_MOUSE_LL, proc,
                    GetModuleHandle(curModule.ModuleName), 0);
            }
        }

        private delegate IntPtr LowLevelMouseProc(int nCode, IntPtr wParam, IntPtr lParam);

        private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
        {
            int xPos = 0;
            int yPos = 0;

            if (nCode >= 0 && MouseMessages.WM_MOUSEMOVE == (MouseMessages)wParam)
            {    
                xPos = GET_X_LPARAM(lParam); 
                yPos = GET_Y_LPARAM(lParam);

                //do stuff with xPos and yPos
            }
            return CallNextHookEx(_hookID, nCode, wParam, lParam);
        }


        private enum MouseMessages
        {
            WM_MOUSEMOVE = 0x0200
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct POINT
        {
            public int x;
            public int y;
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct MSLLHOOKSTRUCT
        {
            public POINT pt;
            public int mouseData;
            public int flags;
            public int time;
            public IntPtr dwExtraInfo;
        }

        public struct INPUT
        {
            public int type;
            public MOUSEINPUT mi;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct MOUSEINPUT
        {
            public int dx;
            public int dy;
            public int mouseData;
            public uint dwFlags;
            public int time;
            public int dwExtraInfo;
        }



        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr SetWindowsHookEx(int idHook,
            LowLevelMouseProc lpfn, IntPtr hMod, uint dwThreadId);

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool UnhookWindowsHookEx(IntPtr hhk);

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode,
            IntPtr wParam, IntPtr lParam);

        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr GetModuleHandle(string lpModuleName);

    }

}