我从来都不记得我是怎么做到的,因为它很少出现在我身上。但是在C或c++中,从标准输入中读取字符而不等待换行符(按enter)的最佳方法是什么?

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。


当前回答

C和c++对I/O有一个非常抽象的看法,没有标准的方法来做你想做的事情。有从标准输入流中获取字符的标准方法(如果有的话),这两种语言都没有定义其他任何方法。因此,任何答案都必须是特定于平台的,可能不仅取决于操作系统,还取决于软件框架。

这里有一些合理的猜测,但如果不知道目标环境是什么,就无法回答您的问题。

其他回答

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; 
}

Ncurses提供了一个很好的方法来做到这一点! 这也是我的第一篇文章(我记得),所以欢迎任何评论。我会欣赏有用的,但都是受欢迎的!

编译: g++ -std=c++11 -pthread -lncurses .cpp -o

#include <iostream>
#include <ncurses.h>
#include <future>

char get_keyboard_input();

int main(int argc, char *argv[])
{
    initscr();
    raw();
    noecho();
    keypad(stdscr,true);

    auto f = std::async(std::launch::async, get_keyboard_input);
    while (f.wait_for(std::chrono::milliseconds(20)) != std::future_status::ready)
    {
        // do some work
    }

    endwin();
    std::cout << "returned: " << f.get() << std::endl;
    return 0;
}

char get_keyboard_input()
{
    char input = '0';
    while(input != 'q')
    {
        input = getch();
    }
    return input;
}

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

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。

我总是想要一个循环读取我的输入而不按返回键。 这对我很管用。

#include<stdio.h>
 main()
 {
   char ch;
    system("stty raw");//seting the terminal in raw mode
    while(1)
     {
     ch=getchar();
      if(ch=='~'){          //terminate or come out of raw mode on "~" pressed
      system("stty cooked");
     //while(1);//you may still run the code 
     exit(0); //or terminate
     }
       printf("you pressed %c\n ",ch);  //write rest code here
      }

    }