我怎么知道按下哪个键？

Question

我想知道如何知道键盘上按下了哪个键。 阅读了几个有关GetAsyncKeyState（）的网站，但我仍然不了解此功能的工作原理。 任何人都请举例说明。

Answer 1

对于Windows，可以使用以下命令：

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>

int main()
{
    while(1)
    {
        if (GetAsyncKeyState(VK_DELETE))
        {
            printf("Delete has been pressed");
        }
    }
}

Answer 2

有关更多虚拟密钥代码，请访问此（ https://msdn.microsoft.com/zh-cn/library/dd375731(v=vs.85).aspx ）

  #include <iostream> 
  #include <windows.h> 
  #include <winuser.h> 
     using namespace std; 
     int Stroke (int key_stroke);

    int main() 
    { 
       char i;
       while (1)
        {
           for(i = 8; i <= 190; i++)
            {
              if (GetAsyncKeyState(i) == -32767)
              Stroke (i); 
             }
        }
       return 0;
     }

   int Stroke (int key_stroke)
   {
     if ( (key_stroke == 1) || (key_stroke == 2) )
     return 0;
     if (key_stroke == 8)
     printf("%s\n", "[BACKSPACE]"); 
     else if (key_stroke == 13)
     printf("%s\n", "[ENTER]\n"); 
     else if (key_stroke == 32)
     printf("%s\n", "[SPACE]");
     else if (key_stroke == VK_TAB) 
     printf("%s\n", "[TAB]");
     else if (key_stroke == VK_SHIFT)
     printf("%s\n", "[SHIFT]");
     else if (key_stroke == VK_CONTROL)
     printf("%s\n", "[CONTROL]");
     else if (key_stroke == VK_ESCAPE)
     printf("%s\n", "[ESCAPE]");
     else if (key_stroke == VK_END)
     printf("%s\n", "[END]");
     else if (key_stroke == VK_HOME)
     printf("%s\n", "[HOME]");
    else if (key_stroke == VK_LEFT)
    printf("%s\n", "[LEFT]");
    else if (key_stroke == VK_UP)
    printf("%s\n", "[UP]");
    else if (key_stroke == VK_RIGHT)
    printf("%s\n", "[RIGHT]");
    else if (key_stroke == VK_DOWN)
    printf("%s\n", "[DOWN]");
    else if (key_stroke == VK_DELETE)
    printf("%s\n", "[DEL]");
    else if (key_stroke == 190 || key_stroke == 110)
    printf("%s\n", ".");
    else
    printf("%s\n", &key_stroke);
    return 0;
 }