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我有一个表单，它就像一个下拉菜单，我显示非模态。我在表单上附加了一个鼠标钩子，以确定何时从表单中单击鼠标，以便我知道关闭它 - 通过设置Visible = False.

因为我希望HookProc处理最后一次单击，所以在确定我的事件处理程序已返回到 HookProc 之前，我无法处理 Hook 或我的 Dropdown。

这有点难以解释，但我希望下面的代码让它更清楚一点：-

//Loop to display the dropdown.
Dim dd as New DropDown
dd.Visible = True
Do While dd.Visible
    Application.DoEvents()
    NativeMethods.MsgWaitForMultipleObjectsEx(0, IntPtr.Zero, 250, &HFF, 4)
Loop
// I want to dispose dd now, but how can I be sure that e.Handled (See below)
// has been returned to HookProc?

//A handler within dropdown to determine what to do with the mouse click.
Private Sub DropDown_MouseHookClick(ByVal sender As Object, ByVal e As MouseClickEventArgs)
    If IWantToCloseTheDropDown Then
        e.Handled = True
        MyHook.UnHook
        Me.Visible = False
    End If
    // All done, e.Handled is returned to HookProc.
    // But which happens first? Will e.Handled arrive at HookProc first, or will
    // the form display loop, above, notice that Visible is now False?
End Sub

//The main part of the hooking class.
Public Function MouseHookProc(ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
    Dim MyMouseHookStruct As MouseHookStruct = DirectCast(Marshal.PtrToStructure(lParam, GetType(MouseHookStruct)), MouseHookStruct)
    If nCode < 0 Then
        Return CallNextHookEx(hHook, nCode, wParam, lParam)
    Else
        Dim handle As Integer = MyMouseHookStruct.hwnd
        Dim c As Control = Control.FromHandle(New IntPtr(handle))
        If MouseUpOrDown Then
            Dim e As MouseHookClickEventArgs
            OnMouseClick(e)
            If e.Handled Then
                Return 1
            EndIf
        End If
        Return CallNextHookEx(hHook, nCode, wParam, lParam)
    End If
End Function
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2 回答 2

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为什么不只处理焦点事件？Form_LostFocus 会在他们关注另一个控件/表单时告诉您。此时您可以隐藏您的表单。

鼠标钩子对于检测表单是否有焦点似乎有点过分了。

于 2009-11-18T23:21:22.430 回答
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您正在绕过 .NET 机制来处理 Windows 事件

您应该不需要任何本机来处理 WinForms。此外，整个代码都是垃圾收集的，所以你做不应该担心删除钩子

您可能想查看form.deactivate事件

于 2009-11-18T23:43:09.867 回答