从另一个应用程序获取按钮句柄

Question

我有一个程序需要将 BM_CLICK 消息发送到另一个应用程序按钮。 我可以获取父窗口句柄，但是当我尝试获取按钮句柄时，如果总是返回 0，

我从 Spy++ 获取了按钮标题名称和按钮类型，这似乎是正确的，但我知道我一定弄错了。下面是我的代码

 public const Int BM_CLICK = 0x00F5;

 [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr SendMessage(IntPtr hwnd, uint Msg, IntPtr wParam, IntPtr lParam);

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        static extern IntPtr FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter, string lpszClass, string lpszWindow);



private void button1_Click(object sender, EventArgs e)
{
    Process[] processes = Process.GetProcessesByName("QSXer");

    foreach (Process p in processes)
    {
        ////the Button's Caption is "Send" and it is a "Button".  
        IntPtr ButtonHandle = FindWindowEx(p.MainWindowHandle, IntPtr.Zero, "Button", "Send");
       //ButtonHandle is always zero thats where I think the problem is 
    SendMessage(ButtonHandle, BM_CLICK, IntPtr.Zero, IntPtr.Zero);

    }

}

Spy 屏幕截图

Answer 1

尝试为窗口文本传递 null，然后尝试查找任何按钮：

IntPtr ButtonHandle = FindWindowEx(p.MainWindowHandle, IntPtr.Zero, "Button", null);

之后，您可以使用第二个参数和新的调用来多次获取下一个按钮句柄。

另外，您能否尝试检查 Marshal.GetLastWin32Error 以查看错误结果是什么？

Answer 2

试试这个：

IntPtr ButtonHandle = FindWindowEx(p.MainWindowHandle, IntPtr.Zero, null, "Send");

Answer 3

你可以这样做：

//Program finds a window and looks for button in window and clicks it

HWND buttonHandle = 0;

BOOL CALLBACK GetButtonHandle(HWND handle, LPARAM)
{
    char label[100];
    int size = GetWindowTextA(handle, label, sizeof(label));
    if (strcmp(label, "Send") == 0) // your button name
    {
        buttonHandle = handle;
        cout << "button id is: " << handle << endl;
        return false;
    }
    return true;
}

int main()

{
    HWND windowHandle = FindWindowA(NULL, "**Your Window Name**");

    if (windowHandle == NULL)
    {
        cout << "app isn't open." << endl;
    }

    else
    {
        cout << "app is open :) " << endl;
        cout << "ID is: " << windowHandle << endl;
        SetForegroundWindow(windowHandle);
        BOOL ret = EnumChildWindows(windowHandle, GetButtonHandle, 0); //find the button
        cout << buttonHandle << endl;
        if (buttonHandle != 0)
        {
            LRESULT res = SendMessage(buttonHandle, BM_CLICK, 0, 0);
        }
    }
}

这应该可以解决问题。