.net - DoubleClick 事件何时引发，而不是双击鼠标？

Question

The documentation for the MouseDoubleClick event州

Important

DoubleClick events are logically higher-level events of a control. They may be raised by other user actions, such as shortcut key combinations.

但是，我一直无法找到在未引发 MouseDoubleClick 的情况下引发 DoubleClick 事件的控件，并且 the documentation for DoubleClick event也没有提到任何东西。什么时候使用？

Answer 1

某些情况下您需要鼠标属性(位置、点击...)，因此您使用 mousedoubleclicks 事件，在其他情况下您不需要它们，因此系统可以节省一些字节并提高性能。

例如，下面的应用程序几乎是纯 GDI，所以当我单击某个地方时，它非常重要，以至于我拥有鼠标属性...

更新

你是对的:

1:没有引发 doubleclick 和 mousedoubleclick 的情况，反之亦然，因为我反编译了 .Net 3.5 中的控件类，发现唯一引发拖曳事件的地方是在同一个地方 onmouseup 有一些条件:

private void WmMouseUp(ref Message m, MouseButtons button, int clicks)
{
    try
    {
        int x = NativeMethods.Util.SignedLOWORD(m.LParam);
        int y = NativeMethods.Util.SignedHIWORD(m.LParam);
        Point p = new Point(x, y);
        p = this.PointToScreen(p);
        if (!this.GetStyle(ControlStyles.UserMouse))
        {
            this.DefWndProc(ref m);
        }
        else if (button == MouseButtons.Right)
        {
            this.SendMessage(0x7b, this.Handle, NativeMethods.Util.MAKELPARAM(p.X, p.Y));
        }
        bool flag = false;
        if ((((this.controlStyle & ControlStyles.StandardClick) == ControlStyles.StandardClick) && this.GetState(0x8000000)) && (!this.IsDisposed && (UnsafeNativeMethods.WindowFromPoint(p.X, p.Y) == this.Handle)))
        {
            flag = true;
        }
        if (flag && !this.ValidationCancelled)
        {
            if (!this.GetState(0x4000000))
            {
                this.OnClick(new MouseEventArgs(button, clicks, NativeMethods.Util.SignedLOWORD(m.LParam), NativeMethods.Util.SignedHIWORD(m.LParam), 0));
                this.OnMouseClick(new MouseEventArgs(button, clicks, NativeMethods.Util.SignedLOWORD(m.LParam), NativeMethods.Util.SignedHIWORD(m.LParam), 0));
            }
            else
            {
                this.OnDoubleClick(new MouseEventArgs(button, 2, NativeMethods.Util.SignedLOWORD(m.LParam), NativeMethods.Util.SignedHIWORD(m.LParam), 0));
                this.OnMouseDoubleClick(new MouseEventArgs(button, 2, NativeMethods.Util.SignedLOWORD(m.LParam), NativeMethods.Util.SignedHIWORD(m.LParam), 0));
            }
        }
        this.OnMouseUp(new MouseEventArgs(button, clicks, NativeMethods.Util.SignedLOWORD(m.LParam), NativeMethods.Util.SignedHIWORD(m.LParam), 0));
    }
    finally
    {
        this.SetState(0x4000000, false);
        this.SetState(0x8000000, false);
        this.SetState(0x10000000, false);
        this.CaptureInternal = false;
    }
}

2:如果不存在处理程序，则不调用处理程序调用:

[EditorBrowsable(EditorBrowsableState.Advanced)]
protected virtual void OnMouseDoubleClick(MouseEventArgs e)
{
    MouseEventHandler handler = (MouseEventHandler) base.Events[EventMouseDoubleClick];
    if (handler != null)
    {
        handler(this, e);
    }
}