How to get control under mouse cursor? [duplicate]

I have form with few buttons and I want to know what button is under cursor now.

P.S. Maybe it's duplicate, but I can't find answer to this question.

Have a look at GetChildAtPoint. You will have to do some extra work if the controls are contained in a container, see Control.PointToClient.

Maybe GetChildAtPoint and PointToClient is the first idea for most people. I also used it first. But, GetChildAtPoint doesn't work properly with invisible or overlapped controls. Here's a well-working code and it manages those situations.

using System.Drawing;
using System.Windows.Forms;

public static Control FindControlAtPoint(Control container, Point pos)
{
    Control child;
    foreach (Control c in container.Controls)
    {
        if (c.Visible && c.Bounds.Contains(pos))
        {
            child = FindControlAtPoint(c, new Point(pos.X - c.Left, pos.Y - c.Top));
            if (child == null) return c;
            else return child;
        }
    }
    return null;
}

public static Control FindControlAtCursor(Form form)
{
    Point pos = Cursor.Position;
    if (form.Bounds.Contains(pos))
        return FindControlAtPoint(form, form.PointToClient(pos));
    return null;
}

This will give you the control right under the cursor.

// This getYoungestChildUnderMouse(Control) method will recursively navigate a       
// control tree and return the deepest non-container control found under the cursor.
// It will return null if there is no control under the mouse (the mouse is off the
// form, or in an empty area of the form).
// For example, this statement would output the name of the control under the mouse
// pointer (assuming it is in some method of Windows.Form class):
// 
// Console.Writeline(ControlNavigatorHelper.getYoungestChildUnderMouseControl(this).Name);


    public class ControlNavigationHelper
    {
        public static Control getYoungestChildUnderMouse(Control topControl)
        {
            return ControlNavigationHelper.getYoungestChildAtDesktopPoint(topControl, System.Windows.Forms.Cursor.Position);
        }

        private static Control getYoungestChildAtDesktopPoint(Control topControl, System.Drawing.Point desktopPoint)
        {
            Control foundControl = topControl.GetChildAtPoint(topControl.PointToClient(desktopPoint));
            if ((foundControl != null) && (foundControl.HasChildren))
                return getYoungestChildAtDesktopPoint(foundControl, desktopPoint);
            else
                return foundControl;
        }
    }