You can do it portably using SDL (the Simple DirectMedia Library), though I suspect you may not like its behavior. When I tried it, I had to have SDL create a new video window (even though I didn't need it for my program) and have this window "grab" almost all keyboard and mouse input (which was okay for my usage but could be annoying or unworkable in other situations). I suspect it's overkill and not worth it unless complete portability is a must--otherwise try one of the other suggested solutions.

顺便说一下，这将分别提供按键和释放事件，如果你喜欢的话。

我在另一个论坛上发现了这个，当时我想解决同样的问题。根据我的发现，我做了一些修改。效果很好。我运行的是OS X，所以如果你运行的是微软，你需要找到正确的system()命令来切换到raw和cooked模式。

#include <iostream> 
#include <stdio.h>  
using namespace std;  

int main() { 
  // Output prompt 
  cout << "Press any key to continue..." << endl; 

  // Set terminal to raw mode 
  system("stty raw"); 

  // Wait for single character 
  char input = getchar(); 

  // Echo input:
  cout << "--" << input << "--";

  // Reset terminal to normal "cooked" mode 
  system("stty cooked"); 

  // And we're out of here 
  return 0; 
}

#include <conio.h>

if (kbhit() != 0) {
    cout << getch() << endl;
}

它使用kbhit()来检查键盘是否被按下，并使用getch()来获取被按下的字符。

管道演示:如何从C语言的系统调用管道读取键盘按键

理想情况下，它也不会将输入字符回显到屏幕上。我只是想在不影响控制台屏幕的情况下捕捉击键。

要在Linux上做到这一点，您可以使用以下bash命令:

read -sn1 c && printf "You Pressed: %s\n" "$c"

请看我在这里的回答关于这个的详细信息:shell脚本响应按键。

因此，要在Linux上的C或c++中做到这一点，您只需要通过使用popen()和fgets()的管道通过系统调用调用上面的bash命令，这样您就可以从bash命令读取输出。

下面是一个完整的例子，在Linux上运行良好的C和c++:

read_system_call_via_pipe__keypress.c:

#include <stdbool.h> // For `true` (`1`) and `false` (`0`) macros in C
#include <stdint.h>  // For `uint8_t`, `int8_t`, etc.
#include <stdio.h>   // For `printf()`
#include <stdlib.h>

#define BUFSIZE 32

// Read a keyboard key press and return the character pressed, or a negative
// number in the event of an error.
// NB: for help reading output from system calls, see here:
//  1. https://stackoverflow.com/a/28971647/4561887
//  2. https://stackoverflow.com/a/18297075/4561887
char getKeypress()
{
    // This bash cmd is from my answer here:
    // https://stackoverflow.com/a/70979348/4561887
    const char* cmd = "bash -c 'read -s -n1 c && printf \"%s\" \"$c\"'";
    FILE *fp = popen(cmd, "r");
    if (fp == NULL)
    {
        printf("\nError opening pipe!\n");
        return -1;
    }

    char buf[BUFSIZE] = {0};
    char* retval1 = fgets(buf, BUFSIZE, fp);
    if (retval1 == NULL)
    {
        printf("\nFailed to read cmd response.\n");
        return -2;
    }

    // See meaning of this return value here:
    // https://stackoverflow.com/questions/43116/how-can-i-run-an-external-program-from-c-and-parse-its-output/28971647#comment60311936_28971647
    int retval2 = pclose(fp);
    if (retval2 == -1)
    {
        printf("\nError obtaining the cmd's exit status code.\n");
        return -3;
    }
    else if (retval2 != 0)
    {
        printf("\nCommand exited with exit status code %i.\n", retval2);
        return -4;
    }

    char keyPressed = buf[0];
    return keyPressed;
}

// int main(int argc, char *argv[])  // alternative prototype
int main()
{
    printf("Press any key to continue: ");
    fflush(stdout);
    char keyPressed = getKeypress();
    if (keyPressed > 0)
    {
        printf("\nKey pressed = %c\n", keyPressed);
    }

    return 0;
}

C和c++编译和运行命令是下面输出的一部分。下面是一些演示:

在C:

eRCaGuy_hello_world/c$ gcc -Wall -Wextra -Werror -O3 -std=gnu17 read_keypress_system_call.c -o bin/a && bin/a
Press any key to continue:
Key pressed = P

或，在c++中:

eRCaGuy_hello_world/c$ g++ -Wall -Wextra -Werror -O3 -std=c++17 read_keypress_system_call.c -o bin/a && bin/a
Press any key to continue:
Key pressed = u

参见:

要更进一步，请参阅我在这里的另一个回答，我一次检测并解析3个字符，以便检测方向键的向上、向下、向左或向右:在C语言中读取键按下。方向键，Enter键

引用:

How I learned to read from a pipe to get system call output: How can I run an external program from C and parse its output? Is there a way to obtain the output of a linux command(like ifconfig) on a .txt file using a C program? [duplicate] How to compile and use popen() in C: use -std=gnu17 instead of -std=c17: popen implicitly declared even though #include <stdio.h> is added [my answer] How to read without blocking, via bash: shell script respond to keypress [my answer] How do I read in the Enter key as an input in C?

关于这个话题的3个问题

从标准输入中捕获字符，而不需要等待按enter键 C非阻塞键盘输入 如何避免按Enter与getchar()只为读取单个字符?

我也遇到过同样的问题。这里是一个小的解决方案为windows控制台使用cygwing++与if(GetKeyState(keycode) & bitANDcompare){};

#include <windows.h>
#include <fstream>
#include <iostream>

using namespace std;
void clear() {
    COORD topLeft  = { 0, 0 };
    HANDLE console = GetStdHandle(STD_OUTPUT_HANDLE);
    CONSOLE_SCREEN_BUFFER_INFO screen;
    DWORD written;

    GetConsoleScreenBufferInfo(console, &screen);
    FillConsoleOutputCharacterA(
        console, ' ', screen.dwSize.X * screen.dwSize.Y, topLeft, &written
    );
    FillConsoleOutputAttribute(
        console, FOREGROUND_GREEN | FOREGROUND_RED | FOREGROUND_BLUE,
        screen.dwSize.X * screen.dwSize.Y, topLeft, &written
    );
    SetConsoleCursorPosition(console, topLeft);
}

class Keyclick{
    private:
    int key;
    char id;
    public:
    bool keydown = false;
    Keyclick(int key1, char id1){
        key=key1;
        id=id1;
    };
    void watch(){
        if(keydown==false){
            if(GetKeyState(key) & 0x8000 ){
                cout << id;
                cout << "  pressed.\r\n";
                keydown = true;
            }
        }
        if(keydown == true){
            if(!(GetKeyState(key) & 0x8000)) {
                cout << "released!!!!!!!!!!\r\n";
                keydown = false;
                clear();
            }
        }
    };
};

int main()
{
    bool primaryloop =true;
    Keyclick keysp(VK_SPACE,'S');
    Keyclick keyw(0x57,'w');
    Keyclick keya(0x41,'a');
    Keyclick keys(0x53,'s');
    Keyclick keyd(0x44,'d');
    Keyclick keyesc(VK_ESCAPE,'E');
    
    while(primaryloop){
        keysp.watch();
        keyw.watch();
        keya.watch();
        keys.watch();
        keyd.watch();
        keyesc.watch();
        
        if(keyesc.keydown){
            primaryloop=false;
        };      
    }
    return 0;
}

https://github.com/wark77/windows_console_keypoller/blob/main/getkeystate_SOLUTION01.cpp

如果你在windows上，你可以使用PeekConsoleInput来检测是否有任何输入，

HANDLE handle = GetStdHandle(STD_INPUT_HANDLE);
DWORD events;
INPUT_RECORD buffer;
PeekConsoleInput( handle, &buffer, 1, &events );

然后使用ReadConsoleInput“消费”输入字符..

PeekConsoleInput(handle, &buffer, 1, &events);
if(events > 0)
{
    ReadConsoleInput(handle, &buffer, 1, &events);  
    return buffer.Event.KeyEvent.wVirtualKeyCode;
}
else return 0

老实说，这是从一些旧的代码，我有，所以你必须拨弄它一点。

最酷的是它读取输入时没有任何提示，所以字符根本不会显示出来。