Question

我对SetWindowPos函数有一个奇怪的问题。此功能用于通过以下代码将应用程序置于顶部：

                if (!SetWindowPos(this.Handle, HWND_TOPMOST, 0, 0, 0, 0, NO_FOCUS_FLAGS))
                    Log.LogError("SetWindowPos HWND_TOPMOST returned false");

                if (!SetWindowPos(this.Handle, HWND_NOTOPMOST, 0, 0, 0, 0, NO_FOCUS_FLAGS))
                    Log.LogError("SetWindowPos HWND_NOTOPMOST returned false");

在大多数情况下，我能够从Windows中看到正常的事件堆栈：

WndProc(): m - msg=0x46 (WM_WINDOWPOSCHANGING) hwnd=0x21016 wparam=0x0 lparam=0x20d688 result=0x0
WndProc(): m - msg=0x14 (WM_ERASEBKGND) hwnd=0x21016 wparam=0xffffffffc60128f1 lparam=0x0 result=0x0
WndProc(): m - msg=0x135 (WM_CTLCOLORBTN) hwnd=0x21016 wparam=0xffffffff950128ae lparam=0x40f2e result=0x0
WndProc(): m - msg=0x47 (WM_WINDOWPOSCHANGED) hwnd=0x21016 wparam=0x0 lparam=0x20d688 result=0x0
WndProc(): m - msg=0x46 (WM_WINDOWPOSCHANGING) hwnd=0x21016 wparam=0x0 lparam=0x20d688 result=0x0
WndProc(): m - msg=0x135 (WM_CTLCOLORBTN) hwnd=0x21016 wparam=0xffffffffc60128f1 lparam=0x40f2e result=0x0
WndProc(): m - msg=0x47 (WM_WINDOWPOSCHANGED) hwnd=0x21016 wparam=0x0 lparam=0x20d688 result=0x0

但有时我得到以下内容：

WndProc(): m - msg=0x46 (WM_WINDOWPOSCHANGING) hwnd=0x104f4 wparam=0x0 lparam=0x3ad6cc result=0x0
WndProc(): m - msg=0x14 (WM_ERASEBKGND) hwnd=0x104f4 wparam=0x26012ce9 lparam=0x0 result=0x0
WndProc(): m - msg=0x135 (WM_CTLCOLORBTN) hwnd=0x104f4 wparam=0x90127a1 lparam=0x105de result=0x0
WndProc(): m - msg=0x46 (WM_WINDOWPOSCHANGING) hwnd=0x104f4 wparam=0x0 lparam=0x3ad6cc result=0x0

在这种情况下，SetWindowPos（）返回成功，但应用程序没有达到顶峰。

这个问题太难重现，我无法轻易测试。

有谁知道WM_WINDOWPOSCHANGED缺少什么？我该如何解决这个问题？

提前致谢！

Answer 1

让我把任何程序放在前面的最有效的方法是：

P / Invoke - AttachThreadInput
P / Invoke - BringWindowToTop
P / Invoke - 带参数SW_SHOW的ShowWindow

它每次都适用于我，它从我尝试的任何应用程序中窃取焦点。就像全屏显示Citrix或远程桌面一样，我的程序就在前台。

诀窍是制造窗户＆＃34;思考＆＃34;我们的进程和目标窗口（hwnd）通过附加线程（使用AttachThreadInput API）和使用替代API来关联：BringWindowToTop。

public static void AttachedThreadInputAction(Action action)
{
    var foreThread = GetWindowThreadProcessId(GetForegroundWindow(), IntPtr.Zero);
    var appThread = GetCurrentThreadId();
    bool threadsAttached = false;
    try
    {
        threadsAttached =
            foreThread == appThread ||
            AttachThreadInput(foreThread, appThread, true);
        if (threadsAttached) action();
        else throw new ThreadStateException("AttachThreadInput failed.");
    }
    finally
    {
        if (threadsAttached)
            AttachThreadInput(foreThread, appThread, false);
    }
}

用法：

public const uint SW_SHOW = 5;

///<summary>
/// Forces the window to foreground.
///</summary>
///<hwnd>The HWND.</param>
public static void ForceWindowToForeground(IntPtr hwnd)
{
    AttachedThreadInputAction(
        () =>
        {
            BringWindowToTop(hwnd);
            ShowWindow(hwnd, SW_SHOW);
        });
}

SetWindowPos不会将应用程序放在首位

1 个答案: