Question

我尝试从VSTO加载项继承Excel 2010的主窗口。当程序关闭时，这会导致异常和Excel崩溃。

所以我创建了一个小例子来重现我机器上的错误。显然，当调用WM_CLOSE时，对CallWindowProc的调用会抛出一个ThreadAbortException。

Public Class ThisAddIn

Private Const GWL_WNDPROC As Integer = -4

Private Delegate Function WndProcDelegate( _
    ByVal hWnd As IntPtr, _
    ByVal msg As Int32, _
    ByVal wParam As Int32, _
    ByVal lParam As Int32) As Int32

Private Declare Function SetWindowLong _
    Lib "user32.dll" Alias "SetWindowLongA" ( _
        ByVal hWnd As IntPtr, _
        ByVal nIndex As Int32, _
        ByVal dwNewLong As IntPtr) As Int32

Private Declare Function SetWindowLong _
    Lib "user32.dll" Alias "SetWindowLongA" ( _
        ByVal hWnd As IntPtr, _
        ByVal nIndex As Int32, _
        ByVal dwNewLong As WndProcDelegate) As IntPtr

Private Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" _
    (ByVal lpPrevWndFunc As IntPtr, ByVal hWnd As IntPtr, ByVal msg As Integer, _
     ByVal wParam As Integer, ByVal lParam As Integer) As Integer

<System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.FunctionPtr)> _
    Private mWndProc As WndProcDelegate

Private mPrevWindowProc As IntPtr

Private Sub ThisAddIn_Startup(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Startup
    mWndProc = New WndProcDelegate(AddressOf SubWndProc)

    mPrevWindowProc = SetWindowLong(New IntPtr(Application.Hwnd), GWL_WNDPROC, mWndProc)
End Sub

Private Sub ThisAddIn_Shutdown(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Shutdown
    SetWindowLong(New IntPtr(Application.Hwnd), GWL_WNDPROC, mPrevWindowProc)
End Sub

Private Function SubWndProc( _
        ByVal hWnd As IntPtr, _
        ByVal msg As Int32, _
        ByVal wParam As Int32, _
        ByVal lParam As Int32) As Int32

    Try
        Return CallWindowProc(mPrevWindowProc, hWnd, msg, wParam, lParam)
    Catch ex As Exception
        Windows.Forms.MessageBox.Show(ex.ToString)
    End Try
End Function

End Class

这是发生在我的机器上还是我做错了什么？

顺便说一句，如果我在WM_CLOSE或WM_DESTROY事件中恢复WndProc没有任何区别，Excel会崩溃。

Excel 2010，Windows XP，VS 2008

在.NET中继承Excel 2010时出现异常

0 个答案: