drag and drop datagridview entire row

private Rectangle dragBoxFromMouseDown;
        private int rowIndexFromMouseDown;
        private int rowIndexOfItemUnderMouseToDrop;

private void dgvPARs_MouseMove(object sender, MouseEventArgs e)
        {


            if ((e.Button & MouseButtons.Left) == MouseButtons.Left)
            {
                // If the mouse moves outside the rectangle, start the drag.
                if (dragBoxFromMouseDown != Rectangle.Empty &&
                    !dragBoxFromMouseDown.Contains(e.X, e.Y))
                {

                    // Proceed with the drag and drop, passing in the list item.                    
                    DragDropEffects dropEffect = dgvPARs.DoDragDrop(
                    dgvPARs.Rows[rowIndexFromMouseDown],
                    DragDropEffects.Move);
                }
            }

        }

        private void dgvPARs_MouseDown(object sender, MouseEventArgs e)
        {


            rowIndexFromMouseDown = dgvPARs.HitTest(e.X, e.Y).RowIndex;
            if (rowIndexFromMouseDown != -1)
            {
                // Remember the point where the mouse down occurred. 
                // The DragSize indicates the size that the mouse can move 
                // before a drag event should be started.                
                Size dragSize = SystemInformation.DragSize;

                // Create a rectangle using the DragSize, with the mouse position being
                // at the center of the rectangle.
                dragBoxFromMouseDown = new Rectangle(new Point(e.X - (dragSize.Width / 2),
                                                               e.Y - (dragSize.Height / 2)),
                                    dragSize);
            }
            else
                // Reset the rectangle if the mouse is not over an item in the ListBox.
                dragBoxFromMouseDown = Rectangle.Empty;

        }

        private void dgvPARs_DragOver(object sender, DragEventArgs e)
        {


            e.Effect = DragDropEffects.Move;

        }

        private void dgvPARs_DragDrop(object sender, DragEventArgs e)
        {


            Point clientPoint = dgvPARs.PointToClient(new Point(e.X, e.Y));

            // Get the row index of the item the mouse is below. 
            rowIndexOfItemUnderMouseToDrop =
                dgvPARs.HitTest(clientPoint.X, clientPoint.Y).RowIndex;

            // If the drag operation was a move then remove and insert the row.
            if (e.Effect == DragDropEffects.Move)
            {
                DataGridViewRow rowToMove = e.Data.GetData(
                    typeof(DataGridViewRow)) as DataGridViewRow;
                dgvPARs.Rows.RemoveAt(rowIndexFromMouseDown);
                dgvPARs.Rows.Insert(rowIndexOfItemUnderMouseToDrop, rowToMove);

            }

        }