WPF 获取某个窗口的所有子窗口

如果不用到 Win32 方法，可以尝试遍历所有窗口获取 Owner 判断，不过此方法仅仅适合只有一个主线程

通过 Win32 的 EnumChildWindows 可以拿到某个窗口句柄的所有子窗口，大概用法如下，先定义一个辅助类

public class WindowHandleInfo
{
    public static List<IntPtr> GetAllChildHandles(IntPtr handle)
    {
        List<IntPtr> childHandles = new List<IntPtr>();
 
        GCHandle gcChildhandlesList = GCHandle.Alloc(childHandles);
        IntPtr pointerChildHandlesList = GCHandle.ToIntPtr(gcChildhandlesList);
 
        try
        {
            EnumWindowProc childProc = new EnumWindowProc(EnumWindow);
            EnumChildWindows(handle, childProc, pointerChildHandlesList);
        }
        finally
        {
            gcChildhandlesList.Free();
        }
 
        return childHandles;
    }

    private delegate bool EnumWindowProc(IntPtr hwnd, IntPtr lParam);
 
    [DllImport("user32")]
    [return: MarshalAs(UnmanagedType.Bool)]
    private static extern bool EnumChildWindows(IntPtr window, EnumWindowProc callback, IntPtr lParam);
 
    private static bool EnumWindow(IntPtr hWnd, IntPtr lParam)
    {
        GCHandle gcChildhandlesList = GCHandle.FromIntPtr(lParam);
 
        if (gcChildhandlesList == null || gcChildhandlesList.Target == null)
        {
            return false;
        }
 
        List<IntPtr> childHandles = (List<IntPtr>) gcChildhandlesList.Target;
        childHandles.Add(hWnd);
 
        return true;
    }
}

使用方法是先拿到窗口的句柄，然后传入 GetAllChildHandles 方法，就可以拿到所有子窗口的句柄

            var windowInteropHelper = new WindowInteropHelper(window);
            var hwnd = windowInteropHelper.Handle;
            var childWindowList = WindowHandleInfo.GetAllChildHandles(hwnd);