利用ProcessCmdKey处理键盘移动步长

    /// <summary>
    /// Processes a command key.
    /// </summary>
    /// <param name="msg">A <see cref="Message"/>, passed by reference, that represents the window message to process.</param>
    /// <param name="keyData">One of the <see cref="Keys"/> values that represents the key to process.</param>
    /// <returns><c>true</c> if the character was processed by the control; otherwise, <c>false</c>.</returns>
    [SuppressMessage("StyleCop.CSharp.DocumentationRules", "SA1600:ElementsMustBeDocumented", Justification = "Reviewed.")]
    protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
    {
        bool isDirectionKeyPressed = (keyData == Keys.Right || keyData == Keys.Left || keyData == Keys.Up || keyData == Keys.Down);
        ModifierKeysType mkt = CommonUtil.GetModifierKeysType();
        CommonUtil.OnKeyDown(this, mkt, new KeyEventArgs(keyData));

        return base.ProcessCmdKey(ref msg, keyData);
    }

        public static bool OnKeyDown(DrawArea drawArea, KeyEventArgs e)
        {
            ModifierKeysType mkt = GetModifierKeysType();
            return OnKeyDown(drawArea, mkt, e);
        }

        public static bool OnKeyDown(DrawArea drawArea, ModifierKeysType mkt, KeyEventArgs e)
        {
            bool isShiftCtrlPressed = mkt.HasFlag(ModifierKeysType.CtrlShift);
            bool isShiftPressed = mkt.HasFlag(ModifierKeysType.Shift);
            bool isCtrlPressed = mkt.HasFlag(ModifierKeysType.Ctrl); 
            //Alt键按下时，用于复制对象
            bool isAltPressed = mkt.HasFlag(ModifierKeysType.Alt);
            var delta = (isShiftCtrlPressed) ? 20f : (isShiftPressed ? 10f : (isCtrlPressed ? 3f : 1f));
            var keyData = e.KeyData;
            bool isDirectionKeyPressed = (keyData == Keys.Right || keyData == Keys.Left || keyData == Keys.Up || keyData == Keys.Down);
            Vector2 v2 = GetOffset(e, delta);
            if (!isDirectionKeyPressed)
            {
                if (isAltPressed)
                    drawArea.GraphicsList.CopyAndPasteSelction(v2);
                else
                    MoveSelectedObject(drawArea, v2);
            }
            else
                MoveSelectedObject(drawArea, v2);

            drawArea.Refresh();

            return true;
        }

        public static ModifierKeysType GetModifierKeysType()
        {
            bool isAltPressed = (Control.ModifierKeys & Keys.Alt) == Keys.Alt;
            bool isShiftPressed = (Control.ModifierKeys & Keys.Shift) == Keys.Shift;
            bool isCtrlPressed = (Control.ModifierKeys & Keys.Control) == Keys.Control;

            ModifierKeysType mkt = ModifierKeysType.None;
            if (isAltPressed)
                mkt |= ModifierKeysType.Alt;
            if (isShiftPressed)
                mkt |= ModifierKeysType.Shift;
            if (isCtrlPressed)
                mkt |= ModifierKeysType.Ctrl;

            return mkt;
        }

        /// <summary>
    /// 修饰键类型 Modifier Keys Type
    /// </summary>
    public enum ModifierKeysType
    {
        None=0,
        Alt=1,
        Shift=2,
        Ctrl=4,
        AltShift=Alt | Shift,
        CtrlShift=Ctrl | Shift,
        CtrlAlt=Alt | Ctrl,
        All = Ctrl | Alt | Shift,
    }