Custom Windows Panel

#region Control Event Handlers

private void ControlMouseEnter(object sender, EventArgs e)
{
    var control = (Control) sender;
    _defaultCursor = control.Cursor;

    if (_canEdit && _canMoveControls)
    {
        control.Cursor = Cursors.SizeAll;
    }
}

private void ControlMouseLeave(object sender, EventArgs e)
{
    var control = (Control) sender;
    control.Cursor = _defaultCursor;
}

private void ControlMouseDown(object sender, MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left)
    {
        _isMouseDown = true;
    }

    _hitPoint = e.Location;

    if (_canEdit)
    {
        var control = (Control) sender;
        _tracker.Control = control;
    }
}

private void ControlMouseMove(object sender, MouseEventArgs e)
{
    var control = (Control) sender;

    if (_canEdit && _canMoveControls && _isMouseDown && e.Button == MouseButtons.Left)      
    {
        _dragging = true;
        if (_tracker.Control == control)
            {
                 _tracker.Visible = false;
            }

        control.Left += e.Location.X - _hitPoint.X;
        control.Top += e.Location.Y - _hitPoint.Y;
    }
}

private void ControlMouseUp(object sender, MouseEventArgs e)
{
    _isMouseDown = false;

    // If we are dragging and need to snap, perform the necessary calculations
    if (_canEdit && _canMoveControls && _dragging)
    {
        if (_snapToGrid)
        {
            int xPos = ((Control) sender).Location.X;
            int yPos = ((Control) sender).Location.Y;

            // X axis - horizontal position
            if (xPos%_gridSpacing != 0)
            {
                xPos = ((int) Math.Round(xPos/(decimal) _gridSpacing))*_gridSpacing;
                ((Control) sender).Left = xPos;
            }

            // Y axis - vertical position
            if (yPos%_gridSpacing != 0)
            {
                yPos = ((int) Math.Round(yPos/(decimal) _gridSpacing))*_gridSpacing;
                ((Control) sender).Top = yPos;
            }
        }

        OnLayoutChanged(EventArgs.Empty);
    }


    var control = (Control) sender;

    if (_tracker.Control == control)
    {
        _tracker.Visible = true;

        if (control.Top < 0)
        {
            control.Top = 0;
        }

        if (control.Left < 0)
        {
            control.Left = 0;
        }
    }

    _selectedControl = control;
    OnSelectionChanged(EventArgs.Empty);

    _dragging = false;
}

private void ControlVisibleChanged(object sender, EventArgs e)
{
    if (_canEdit && (_canMoveControls || _canResizeControls))
    {
        var control = (Control) sender;
        if (_tracker.Control == control)
        {
            _tracker.Visible = control.Visible;
        }
    }
}

private void ControlSizeChanged(object sender, EventArgs e)
{
    if (_tracker != null)
    {
        _tracker.SetBounds();
    }
}

private void ControlLocationChanged(object sender, EventArgs e)
{
    if (_tracker != null)
    {
        _tracker.SetBounds();
    }
}

private void ControlHandleDestroyed(object sender, EventArgs e)
{
    _tracker.Control = null;
}

#endregion