如何使用.NET 枚举属于特定进程的所有窗口？

Question

如何使用 c# 找到由特定进程创建的所有窗口？

更新

我需要使用应用程序的PID（进程 ID）枚举属于特定进程的所有窗口。

Answer 1

delegate bool EnumThreadDelegate(IntPtr hWnd, IntPtr lParam);

[DllImport("user32.dll")]
static extern bool EnumThreadWindows(int dwThreadId, EnumThreadDelegate lpfn,
    IntPtr lParam);

static IEnumerable<IntPtr> EnumerateProcessWindowHandles(int processId)
{
    var handles = new List<IntPtr>();

    foreach (ProcessThread thread in Process.GetProcessById(processId).Threads)
        EnumThreadWindows(thread.Id, 
            (hWnd, lParam) => { handles.Add(hWnd); return true; }, IntPtr.Zero);

    return handles;
}

和示例用法：

private const uint WM_GETTEXT = 0x000D;

[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, int wParam, 
    StringBuilder lParam);

[STAThread]
static void Main(string[] args)
{
    foreach (var handle in EnumerateProcessWindowHandles(
        Process.GetProcessesByName("explorer").First().Id))
    {
        StringBuilder message = new StringBuilder(1000);
        SendMessage(handle, WM_GETTEXT, message.Capacity, message);
        Console.WriteLine(message);
    }
}

Answer 2

使用 Win32 API EnumWindows（如果您想要子窗口 EnumChildWindows）），或者您也可以使用 EnumThreadWindows 。

[DllImport("user32.dll", CharSet=CharSet.Auto, SetLastError=true)]
public static extern bool EnumWindows(EnumThreadWindowsCallback callback, IntPtr extraData);

然后通过Win32 APIGetWindowThreadProcessId检查每个窗口属于哪个进程

[DllImport("user32.dll", CharSet=CharSet.Auto, SetLastError=true)]
public static extern int GetWindowThreadProcessId(HandleRef handle, out int processId);

Answer 3

古老的线程，但它让我开始了，所以这里有一个小实用函数，它将找到一个与 lambda（谓词）匹配的子窗口。易于更改返回列表。在谓词中处理多个条件。

    public delegate bool Win32Callback(IntPtr hwnd, IntPtr lParam);

    [DllImport("user32.Dll")]
    [return: MarshalAs(UnmanagedType.Bool)]
    public static extern bool EnumChildWindows(IntPtr parentHandle, Win32Callback callback, IntPtr lParam);

    /// <summary>
    /// Find a child window that matches a set of conditions specified as a Predicate that receives hWnd.  Returns IntPtr.Zero
    /// if the target window not found.  Typical search criteria would be some combination of window attributes such as
    /// ClassName, Title, etc., all of which can be obtained using API functions you will find on pinvoke.net
    /// </summary>
    /// <remarks>
    ///     <para>Example: Find a window with specific title (use Regex.IsMatch for more sophisticated search)</para>
    ///     <code lang="C#"><![CDATA[var foundHandle = Win32.FindWindow(IntPtr.Zero, ptr => Win32.GetWindowText(ptr) == "Dashboard");]]></code>
    /// </remarks>
    /// <param name="parentHandle">Handle to window at the start of the chain.  Passing IntPtr.Zero gives you the top level
    /// window for the current process.  To get windows for other processes, do something similar for the FindWindow
    /// API.</param>
    /// <param name="target">Predicate that takes an hWnd as an IntPtr parameter, and returns True if the window matches.  The
    /// first match is returned, and no further windows are scanned.</param>
    /// <returns> hWnd of the first found window, or IntPtr.Zero on failure </returns>
    public static IntPtr FindWindow(IntPtr parentHandle, Predicate<IntPtr> target) {
        var result = IntPtr.Zero;
        if (parentHandle == IntPtr.Zero)
            parentHandle = Process.GetCurrentProcess().MainWindowHandle;
        EnumChildWindows(parentHandle, (hwnd, param) => {
            if (target(hwnd)) {
                result = hwnd;
                return false;
            }
            return true;
        }, IntPtr.Zero);
        return result;
    }

例子

var foundHandle = Win32.FindWindow(IntPtr.Zero, ptr => Win32.GetWindowText(ptr) == "Dashboard");