c# - 全局挂钩键盘记录问题

Question

它当前将密钥记录到文本框，因此很安全。

问题问题是当我在虚拟机或我朋友的笔记本电脑上运行它时，它在按下一定数量的键（随机）后挂起。它在我的运行得非常好。

http://i34.tinypic.com/29o1im8.jpg

class GlobalKeyboardHook
{


    #region Definition of Structures, Constants and Delegates

    public delegate int KeyboardHookProc(int nCode, int wParam, ref GlobalKeyboardHookStruct lParam);

    public struct GlobalKeyboardHookStruct
    {
        public int vkCode;
        public int scanCode;
        public int flags;
        public int time;
        public int dwExtraInfo;
    }

    const int WM_KEYDOWN = 0x100;
    const int WM_KEYUP = 0x101;
    const int WM_SYSKEYDOWN = 0x104;
    const int WM_SYSKEYUP = 0x105;
    const int WH_KEYBOARD_LL = 13;

    #endregion

    #region Events

    public event KeyEventHandler KeyDown;
    public event KeyEventHandler KeyUp;

    #endregion

    #region Instance Variables

    public List<Keys> HookedKeys = new List<Keys>();
    IntPtr hookHandle = IntPtr.Zero;

    #endregion

    #region DLL Imports

    [DllImport("kernel32.dll")]
    static extern IntPtr LoadLibrary(string lpFileName);

    [DllImport("user32.dll", CharSet = CharSet.Auto,CallingConvention = CallingConvention.StdCall, SetLastError = true)]
    static extern IntPtr SetWindowsHookEx(int hookID, KeyboardHookProc callback, IntPtr hInstance, uint threadID);

    [DllImport("user32.dll", CharSet = CharSet.Auto,CallingConvention = CallingConvention.StdCall, SetLastError = true)]
    static extern bool UnhookWindowsHookEx(IntPtr hookHandle);

    [DllImport("user32.dll", CharSet = CharSet.Auto,CallingConvention = CallingConvention.StdCall)]
    static extern int CallNextHookEx(IntPtr hookHandle, int nCode, int wParam, ref GlobalKeyboardHookStruct lParam);




    #endregion

    #region Public Methods

    public int hookProc(int nCode, int wParam, ref GlobalKeyboardHookStruct lParam)
    {

        if (nCode >= 0)
        {
            Keys key = (Keys)lParam.vkCode;

            if (HookedKeys.Contains(key) == true)
            {
                KeyEventArgs kea = new KeyEventArgs(key);

                    if ((wParam == WM_KEYUP || wParam == WM_SYSKEYUP) && KeyUp != null)
                    {
                        KeyUp(this, kea);
                    }
                    else if ((wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN) && KeyDown != null)
                    {
                        KeyDown(this, kea);
                    }
                    if (kea.Handled) return 1;


            }
        }

     return CallNextHookEx(hookHandle, nCode, wParam, ref lParam);
    }


    public void hook()
    {
            IntPtr hInstance = LoadLibrary("user32");
            hookHandle = SetWindowsHookEx(WH_KEYBOARD_LL, hookProc, hInstance, 0);
    }


    public void unhook()
    {
        UnhookWindowsHookEx(hookHandle);
    }

    #endregion

    #region Constructors and Destructors

    public GlobalKeyboardHook()
    {
        hook();
    }

    ~GlobalKeyboardHook()
    {
        unhook();
    }

    #endregion

Answer 1

尝试在打开“CallbackOnCollectedDelegate”MDA 的情况下调试您的应用程序（调试 -> 异常 -> 托管调试助手 -> 选中“CallbackOnCollectedDelegate”）。

这里的常见错误是，您的挂钩过程的委托在您设置挂钩后由 GC 自动收集（它是作为 P/Invoke 封送处理的一部分创建的SetWindowsHookEx）。GC 收集到委托后，程序在尝试调用回调时崩溃。这也可以解释随机性。

如果这是您的问题，您将看到如下错误：

对类型为“...”的垃圾收集委托进行了回调。这可能会导致应用程序崩溃、损坏和数据丢失。将委托传递给非托管代码时，托管应用程序必须使它们保持活动状态，直到保证它们永远不会被调用。

尝试保留对您的钩子程序的引用作为您班级中的成员，例如：

public delegate int KeyboardHookProc(int nCode, int wParam, ref GlobalKeyboardHookStruct lParam);

public int hookProc(int nCode, int wParam, ref GlobalKeyboardHookStruct lParam)
{
    // ...
}

public void hook()
{
    _hookProc = new KeyboardHookProc(hookProc);
    IntPtr hInstance = LoadLibrary("user32");
    hookHandle = SetWindowsHookEx(WH_KEYBOARD_LL, _hookProc, hInstance, 0);
}

KeyboardHookProc _hookProc;