C# 托管窗口时发生BuildWindowCore错误

我正在尝试在进程中主持另一个进程的窗口。 为此，我使用了如下

HwndHost

：

public class MyHandle : HwndHost
{
    #region User32.dll

    private static Int32 WS_VISIBLE = 0x10000000;
    private static Int32 WS_CHILD = 0x40000000;
    private static Int32 WS_BORDER = 0x00800000;
    private static Int32 GWL_STYLE = -16;

    [DllImport("user32.dll")]
    private static extern int GetWindowThreadProcessId(IntPtr hWnd, IntPtr procid);

    [DllImport("user32.dll")]
    private static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);

    [DllImport("user32.dll", SetLastError = true)]
    private static extern int GetWindowLong(IntPtr hWnd, int nIndex);

    [DllImport("user32")]
    private static extern IntPtr SetParent(IntPtr hWnd, IntPtr hWndParent);
    #endregion
    private Action WindowCoreBuilt = null;

    private IntPtr m_window = IntPtr.Zero;

    public MyHandle(IntPtr window, Action windowCoreBuiltDelegate)
    {
        m_window = window;
        WindowCoreBuilt = windowCoreBuiltDelegate;
    }

    protected override System.Runtime.InteropServices.HandleRef BuildWindowCore(System.Runtime.InteropServices.HandleRef hwndParent)
    {
        int guestStyle = SetWindowLong(m_window, GWL_STYLE, WS_CHILD | WS_BORDER | WS_VISIBLE);
        SetParent(m_window, hwndParent.Handle);

        HandleRef hwnd = new HandleRef(this, m_window);
        InvokeHelper.InvokeDelegate(this.Dispatcher, () => WindowCoreBuilt());
        return hwnd;
    }

    protected override void DestroyWindowCore(HandleRef hwnd)
    {
    }
}

它通常是有效的，但有时我会遇到这样的例外：

System.InvalidOperationException: BuildWindowCore failed to return the hosted child window handle.
   at System.Windows.Interop.HwndHost.BuildWindow(HandleRef hwndParent)
   at System.Windows.Interop.HwndHost.BuildOrReparentWindow()
   at System.Windows.Interop.HwndHost.OnSourceChanged(Object sender, SourceChangedEventArgs e)
   at System.Windows.SourceChangedEventArgs.InvokeEventHandler(Delegate genericHandler, Object genericTarget)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.UIElement.RaiseEvent(RoutedEventArgs e)
   at System.Windows.PresentationSource.UpdateSourceOfElement(DependencyObject doTarget, DependencyObject doAncestor, DependencyObject doOldParent)
   at System.Windows.PresentationSource.OnVisualAncestorChanged(DependencyObject uie, AncestorChangedEventArgs e)
   at System.Windows.UIElement.OnVisualAncestorChanged(Object sender, AncestorChangedEventArgs e)

stacktrace要深入得多，但我认为这与此无关。
我的问题是：
1.是什么原因导致此问题？我如何解决此问题？
2.如何捕获此异常以防止应用程序崩溃？（它发生在我无法访问的系统线程中…）

这是引发异常的特定部分

IsWindow

是函数的直接调用

private void ClearChildControl()
{
    if (null == PlayerPanel)
        return;

    /* this border panel hosts the control of another process */
    PlayerPanel.Child = null;
}

---

我的猜测是，您正在以某种方式从

BuildWindowCore

返回

IntPtr.Zero

句柄。一旦子控件进程崩溃，您需要将主机控件内容清除为null。如果您不这样做，并且您导航离开主机窗口，然后返回主机窗口，或者导致应用程序以任何方式重新绘制，则此BuildWindowCore（）方法将启动并失败

您可以尝试以下技巧，但需要弄清楚控件的宿主进程。拥有Process对象后，可以执行以下操作：

/* on a seperate thread, monitor the process */
Task.Factory.StartNew(() =>
{
    ServiceHostProcess.WaitForExit();
    /* back to the UI thread */
    Application.Current.Dispatcher.Invoke(ClearChildControl);
});

在我的例子中，

ClearChildControl

函数只是将内容清除为null，因此重新绘制尝试甚至不会执行

BuildWindowCore

函数

private void ClearChildControl()
{
    if (null == PlayerPanel)
        return;

    /* this border panel hosts the control of another process */
    PlayerPanel.Child = null;
}

正如“ghord所说，错误来自

HwndHost.BuildWindow

，但是您可以通过确保您提供的HWND不是

IntPtr.Zero

，并且它通过以下方式表示窗口来避免此问题：

[DllImport("user32.dll", ExactSpelling = true, CharSet = CharSet.Auto)]
public static extern bool IsWindow(IntPtr hWnd);

---

但是，如果提供HWND的进程在您为

BuildWindowCore

的调用提供服务时崩溃，那么除了抛出异常或让基类为您执行异常之外，您别无选择。为避免应用程序崩溃，请处理

应用程序。DispatcherUnandledException

并将

处理的
设置为e> 正确
因为这是主要问题。我没有将所有托管儿童清除为空。你救了我一天，马丁！