全局键盘钩

Question

我需要捕获全局键盘消息，所以我使用SetWindowsHookEx（）和WH_KEYBOARD_LL。但它只适用于应用程序关注焦点并且不会触发全局回调。几乎相同的代码与mouse_LL很好（与另一个结构&等）请帮助！

public const int WH_KEYBOARD_LL = 13; 
public const int VK_INSERT = 0x2D; 
public delegate int HookProc(int nCode, IntPtr wParam, IntPtr lParam); 
HookProc KeyboardHookProcedure; 

[DllImport("user32.dll", CharSet = CharSet.Auto, 
    CallingConvention = CallingConvention.StdCall)] 
    public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, 
    IntPtr hInstance, int threadId); 

[DllImport("user32.dll", CharSet = CharSet.Auto, 
    CallingConvention = CallingConvention.StdCall)] 
    public static extern bool UnhookWindowsHookEx(int idHook); 

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

[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)] 
    private static extern IntPtr GetModuleHandle(string lpModuleName); 

[StructLayout(LayoutKind.Sequential)] 
    private struct KBDLLHOOKSTRUCT 
    { 
    public uint vkCode; 
    public uint scanCode; 
    public uint flags; 
    public uint time; 
    public IntPtr dxExtraInfo; 
    } 

private void SetHookKeyboard() 
    { 
    if (kHook == 0) 
    { 
     KeyboardHookLL(); 

     //If the SetWindowsHookEx function fails. 
     if (kHook == 0) 
     { 
      MessageBox.Show("SetWindowsHookEx Failed"); 
      return; 
     } 
     button1.Text = "UnHook Windows Hook"; 
    } 
    else 
    { 
     bool ret = UnhookWindowsHookEx(kHook); 
     //If the UnhookWindowsHookEx function fails. 
     if (ret == false) 
     { 
      MessageBox.Show("UnhookWindowsHookEx Failed"); 
      return; 
     } 
     kHook = 0; 
     this.Text = "Keyboard Hook"; 
    } 
    } 

private void KeyboardHookLL() 
    { 
    KeyboardHookProcedure = new HookProc(MainForm.KeyboardHookProc); 
    kHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardHookProcedure, GetModuleHandle("user32"), 0); 
    } 

public static int KeyboardHookProc(int nCode, IntPtr wParam, IntPtr lParam) 
    { 
    KBDLLHOOKSTRUCT MyKeyboardHookStruct = (KBDLLHOOKSTRUCT)Marshal.PtrToStructure(lParam, typeof(KBDLLHOOKSTRUCT)); 
    if (nCode < 0) 
    { 
     return CallNextHookEx(hHook, nCode, wParam, lParam); 
    } 
    else 
    { 
     Form tempForm = Form.ActiveForm; 
     tempForm.Text = MyKeyboardHookStruct.vkCode.ToString(); 
     if (MyKeyboardHookStruct.vkCode == VK_INSERT) 
     { 
      MainForm.botAlive = false; 
      MessageBox.Show(MainForm.botAlive.ToString()); 
     } 
     return CallNextHookEx(hHook, nCode, wParam, lParam); 
    } 
    } 

Answer 1

问题出在“调试”功能。 Form tempForm = Form.ActiveForm;

Answer 2

幸得乔恩这里：

int vs IntPtr when you have a handle?

我知道这是旧的文章，我离题了一点，但我发现在原来的代码有点阴险的缺点，可转身咬你很在适当的时候很不好（我知道它在我的情况一样）：

[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] 
    public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId); 

应当更优选是：

[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] 
    static extern IntPtr SetWindowsHookEx(HookType hookType, HookProc lpfn, IntPtr hMod, uint dwThreadId); 

对其他签名也应做类似的更改。 虽然Microsoft本身具有以int形式显示SetwindowsHookEx作为返回类型的资源（https://support.microsoft.com/en-us/kb/318804），但您绝不应轻易用其他类型替代'IntPtr'。在这种情况下，'int'仅在32位操作系统中等同于'IntPtr'。在64位平台上，IntPtr是64位，而'int'只保留在32位上，从而打开一整罐蠕虫。使用'int'最糟糕的一个方面是，如果SetWindowsHookEx的返回值不能适应它，那么你很可能最终会出现一个错位的int句柄（它很少见但并不是不可思议的）。

这意味着如果您的应用程序的生命周期超过了您解除挂钩的位置（而不是解除挂钩的调用将始终工作以开始......），那么您最终可能会冻结鼠标和/或键盘，直到主机进程被终止。大多数人都会在这一刻重新启动机器，并完全处置您的应用程序。所有这些“键盘/鼠标冻结”的事情都会发生，因为未配置的钩子需要到达主机应用程序的消息泵，显然这不会发生，因为它所属的组件已经在处理过程中失效了 - wooohoo！

TL; DR：注意您正在使用的p/invoke方法和特别是IntPtrs的签名。