C#Process.MainWindowHandle始终返回IntPtr Zero

Question

这是我的代码:

            using (Process game = Process.Start(new ProcessStartInfo() { 
        FileName="DatabaseCheck.exe",
        RedirectStandardOutput = true,
        CreateNoWindow = true,
        UseShellExecute = false }))
        {
            lblLoad.Text = "Loading";
            int Switch = 0;

            while (game.MainWindowHandle == IntPtr.Zero)
            {
                Switch++;
                if (Switch % 1000 == 0)
                {
                    lblLoad.Text += ".";
                    if (lblLoad.Text.Contains("...."))
                        lblLoad.Text = "Loading.";

                    lblLoad.Update();
                    game.Refresh();
                }
            }

问题是,那个游戏.MainWindowHandle总是IntPtr.Zero.我需要找到运行过程的IntPtr以确认游戏是由启动器启动的,所以我让游戏发送它的IntPtr并让启动器响应它是否正常.但为此,我必须具体了解运行过程的IntPtr.

提前致谢!

Answer 1

主窗口是由当前具有焦点的进程(TopLevel表单)打开的窗口.必须使用该Refresh方法刷新Process对象以获取当前主窗口句柄(如果已更改).

您MainWindowHandle只能为本地计算机上运行的进程获取该属性.MainWindowHandle属性是唯一标识与进程关联的窗口的值.

仅当进程具有图形界面时,进程才具有与其关联的主窗口.如果关联的进程没有主窗口,则MainWindowHandle值为零.对于已隐藏的进程(即,任务栏中不可见的进程),该值也为零.对于在任务栏最右侧的通知区域中显示为图标的进程,情况可能就是如此.

如果您刚刚启动了一个进程并想要使用它的主窗口句柄,请考虑使用WaitForInputIdle方法来允许进程完成启动,确保已创建主窗口句柄.否则,将抛出异常.

Answer 2

while (!proc.HasExited)
{
    proc.Refresh();
    if (proc.MainWindowHandle.ToInt32() != 0)
    {
        return proc.MainWindowHandle;
    }
}

Answer 3

解决方法是枚举所有顶级窗口并检查其进程ID,直到找到匹配项...

    [DllImport("user32.dll")]
    public static extern IntPtr FindWindowEx(IntPtr parentWindow, IntPtr previousChildWindow, string windowClass, string windowTitle);

    [DllImport("user32.dll")]
    private static extern IntPtr GetWindowThreadProcessId(IntPtr window, out int process);

    private IntPtr[] GetProcessWindows(int process) {
        IntPtr[] apRet = (new IntPtr[256]);
        int iCount = 0;
        IntPtr pLast = IntPtr.Zero;
        do {
            pLast = FindWindowEx(IntPtr.Zero, pLast, null, null);
            int iProcess_;
            GetWindowThreadProcessId(pLast, out iProcess_);
            if(iProcess_ == process) apRet[iCount++] = pLast;
        } while(pLast != IntPtr.Zero);
        System.Array.Resize(ref apRet, iCount);
        return apRet;
    }