Ada*_*dam 163 c c++ inputstream
我永远不会记得我是怎么做的,因为它对我来说很少见.但是在C或C++中,从标准输入读取字符而不等待换行符的最佳方法是什么(按回车键).
理想情况下,它也不会将输入字符回显到屏幕上.我只想捕捉击键而不影响控制台屏幕.
Joh*_*itb 91
这在纯C++中是不可能的,因为它过分依赖于可能与stdin连接的终端(它们通常是行缓冲的).但是,你可以使用一个库:
stdin可以在不等待回车键的情况下为您提供角色.我不是常见的Windows开发人员,但我看到我的同学只是包含_getch()并使用它.请参阅维基百科的conio.h.它列出了<conio.h>,在Visual C++中声明已弃用.conio.h功能.(尝试getch()查看其联机帮助页).请参阅维基百科的Curses.如果您的目标是跨平台兼容性,我建议您使用curses.也就是说,我确信有一些功能可以用来关闭线缓冲(我相信这叫做"原始模式",而不是"煮熟模式"(查看getch())).如果我没弄错的话,诅咒会以便携的方式为你处理.
小智 77
在Linux(以及其他类似unix的系统)上,可以通过以下方式完成:
#include <unistd.h>
#include <termios.h>
char getch() {
char buf = 0;
struct termios old = {0};
if (tcgetattr(0, &old) < 0)
perror("tcsetattr()");
old.c_lflag &= ~ICANON;
old.c_lflag &= ~ECHO;
old.c_cc[VMIN] = 1;
old.c_cc[VTIME] = 0;
if (tcsetattr(0, TCSANOW, &old) < 0)
perror("tcsetattr ICANON");
if (read(0, &buf, 1) < 0)
perror ("read()");
old.c_lflag |= ICANON;
old.c_lflag |= ECHO;
if (tcsetattr(0, TCSADRAIN, &old) < 0)
perror ("tcsetattr ~ICANON");
return (buf);
}
基本上你必须关闭规范模式(和回声模式来抑制回声).
cwh*_*iii 17
我在寻找解决同样问题的同时在另一个论坛上找到了这个.我从我发现的东西中修改了一下.它很棒.我正在运行OS X,所以如果你正在运行Microsoft,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;
}
小智 14
CONIO.H
你需要的功能是:
int getch();
Prototype
int _getch(void);
Description
_getch obtains a character from stdin. Input is unbuffered, and this
routine will return as soon as a character is available without
waiting for a carriage return. The character is not echoed to stdout.
_getch bypasses the normal buffering done by getchar and getc. ungetc
cannot be used with _getch.
Synonym
Function: getch
int kbhit();
Description
Checks if a keyboard key has been pressed but not yet read.
Return Value
Returns a non-zero value if a key was pressed. Otherwise, returns 0.
libconio http://sourceforge.net/projects/libconio
要么
conio.h的Linux c ++实现 http://sourceforge.net/projects/linux-conioh
如果您在Windows上,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"消耗"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
说实话,这是来自我的一些旧代码,所以你必须弄清楚它.
但很酷的是,它在没有提示任何内容的情况下读取输入,因此根本不显示字符.
#include <conio.h>
if (kbhit() != 0) {
cout << getch() << endl;
}
这用于kbhit()检查键盘是否被按下并用于getch()获取正在按下的字符.
我使用 kbhit() 查看是否存在字符，然后使用 getchar() 读取数据。在 Windows 上，您可以使用“conio.h”。在 linux 上，您必须实现自己的 kbhit()。
见下面的代码：
// kbhit
#include <stdio.h>
#include <sys/ioctl.h> // For FIONREAD
#include <termios.h>
#include <stdbool.h>
int kbhit(void) {
static bool initflag = false;
static const int STDIN = 0;
if (!initflag) {
// Use termios to turn off line buffering
struct termios term;
tcgetattr(STDIN, &term);
term.c_lflag &= ~ICANON;
tcsetattr(STDIN, TCSANOW, &term);
setbuf(stdin, NULL);
initflag = true;
}
int nbbytes;
ioctl(STDIN, FIONREAD, &nbbytes); // 0 is STDIN
return nbbytes;
}
// main
#include <unistd.h>
int main(int argc, char** argv) {
char c;
//setbuf(stdout, NULL); // Optional: No buffering.
//setbuf(stdin, NULL); // Optional: No buffering.
printf("Press key");
while (!kbhit()) {
printf(".");
fflush(stdout);
sleep(1);
}
c = getchar();
printf("\nChar received:%c\n", c);
printf("Done.\n");
return 0;
}
由于这里以前的解决方案不能跨平台工作并且在使用特殊键时遇到问题，因此这是我的解决方案，它可以在 Windows 和 Linux 上运行，并且使用最少的外部库（对于Windows.hWindows 和sys/ioctl.h+termios.h对于 Linux）。
对于 ASCII 字符（换行符/制表符/空格/退格符/删除符，!"#$%&\'()*+,-./0-9:;<=>?@AZ[]^_`az{|} 〜\ xc3 \ xbc \ xc3 \ xa4 \ xc3 \ x84 \ xc3 \ xb6 \ xc3 \ x96 \ xc3 \ x9c \ xc3 \ x9f \ xc2 \ xb5 \ xc2 \ xb4 \ xc2 \ xa7 \ xc2 \ xb0 \ xc2 \ xb9 \ xc2\xb3\xc2\xb2)，返回 ASCII 代码（正数），对于特殊键（箭头键、向上/向下翻页、pos1/end、转义、插入、F1-F12），返回Windows Virtual-的负数返回键码（负数）。
\n#include <iostream>\n#include <string>\n#include <thread> // contains <chrono>\nusing namespace std;\n\nvoid println(const string& s="") {\n cout << s << endl;\n}\nvoid sleep(const double t) {\n if(t>0.0) this_thread::sleep_for(chrono::milliseconds((int)(1E3*t+0.5)));\n}\n\n\n\n// ASCII codes (key>0): 8 backspace, 9 tab, 10 newline, 27 escape, 127 delete, !"#$%&\'()*+,-./0-9:;<=>?@A-Z[]^_`a-z{|}~\xc3\xbc\xc3\xa4\xc3\x84\xc3\xb6\xc3\x96\xc3\x9c\xc3\x9f\xc2\xb5\xc2\xb4\xc2\xa7\xc2\xb0\xc2\xb9\xc2\xb3\xc2\xb2\n// control key codes (key<0): -38/-40/-37/-39 up/down/left/right arrow, -33/-34 page up/down, -36/-35 pos1/end\n// other key codes (key<0): -45 insert, -144 num lock, -20 caps lock, -91 windows key, -93 kontext menu key, -112 to -123 F1 to F12\n// not working: \xc2\xb9 (251), num lock (-144), caps lock (-20), windows key (-91), kontext menu key (-93), F11 (-122)\n#if defined(_WIN32)\n#define WIN32_LEAN_AND_MEAN\n#define VC_EXTRALEAN\n#include <Windows.h>\nint key_press() { // not working: F11 (-122, toggles fullscreen)\n KEY_EVENT_RECORD keyevent;\n INPUT_RECORD irec;\n DWORD events;\n while(true) {\n ReadConsoleInput(GetStdHandle(STD_INPUT_HANDLE), &irec, 1, &events);\n if(irec.EventType==KEY_EVENT&&((KEY_EVENT_RECORD&)irec.Event).bKeyDown) {\n keyevent = (KEY_EVENT_RECORD&)irec.Event;\n const int ca = (int)keyevent.uChar.AsciiChar;\n const int cv = (int)keyevent.wVirtualKeyCode;\n const int key = ca==0 ? -cv : ca+(ca>0?0:256);\n switch(key) {\n case -16: continue; // disable Shift\n case -17: continue; // disable Ctrl / AltGr\n case -18: continue; // disable Alt / AltGr\n case -220: continue; // disable first detection of "^" key (not "^" symbol)\n case -221: continue; // disable first detection of "`" key (not "`" symbol)\n case -191: continue; // disable AltGr + "#"\n case -52: continue; // disable AltGr + "4"\n case -53: continue; // disable AltGr + "5"\n case -54: continue; // disable AltGr + "6"\n case -12: continue; // disable num block 5 with num lock deactivated\n case 13: return 10; // enter\n case -46: return 127; // delete\n case -49: return 251; // \xc2\xb9\n case 0: continue;\n case 1: continue; // disable Ctrl + a (selects all text)\n case 2: continue; // disable Ctrl + b\n case 3: continue; // disable Ctrl + c (terminates program)\n case 4: continue; // disable Ctrl + d\n case 5: continue; // disable Ctrl + e\n case 6: continue; // disable Ctrl + f (opens search)\n case 7: continue; // disable Ctrl + g\n //case 8: continue; // disable Ctrl + h (ascii for backspace)\n //case 9: continue; // disable Ctrl + i (ascii for tab)\n case 10: continue; // disable Ctrl + j\n case 11: continue; // disable Ctrl + k\n case 12: continue; // disable Ctrl + l\n //case 13: continue; // disable Ctrl + m (breaks console, ascii for new line)\n case 14: continue; // disable Ctrl + n\n case 15: continue; // disable Ctrl + o\n case 16: continue; // disable Ctrl + p\n case 17: continue; // disable Ctrl + q\n case 18: continue; // disable Ctrl + r\n case 19: continue; // disable Ctrl + s\n case 20: continue; // disable Ctrl + t\n case 21: continue; // disable Ctrl + u\n case 22: continue; // disable Ctrl + v (inserts clipboard)\n case 23: continue; // disable Ctrl + w\n case 24: continue; // disable Ctrl + x\n case 25: continue; // disable Ctrl + y\n case 26: continue; // disable Ctrl + z\n default: return key; // any other ASCII/virtual character\n }\n }\n }\n}\n#elif defined(__linux__)\n#include <sys/ioctl.h>\n#include <termios.h>\nint key_press() { // not working: \xc2\xb9 (251), num lock (-144), caps lock (-20), windows key (-91), kontext menu key (-93)\n struct termios term;\n tcgetattr(0, &term);\n while(true) {\n term.c_lflag &= ~(ICANON|ECHO); // turn off line buffering and echoing\n tcsetattr(0, TCSANOW, &term);\n int nbbytes;\n ioctl(0, FIONREAD, &nbbytes); // 0 is STDIN\n while(!nbbytes) {\n sleep(0.01);\n fflush(stdout);\n ioctl(0, FIONREAD, &nbbytes); // 0 is STDIN\n }\n int key = (int)getchar();\n if(key==27||key==194||key==195) { // escape, 194/195 is escape for \xc2\xb0\xc3\x9f\xc2\xb4\xc3\xa4\xc3\xb6\xc3\xbc\xc3\x84\xc3\x96\xc3\x9c\n key = (int)getchar();\n if(key==91) { // [ following escape\n key = (int)getchar(); // get code of next char after \\e[\n if(key==49) { // F5-F8\n key = 62+(int)getchar(); // 53, 55-57\n if(key==115) key++; // F5 code is too low by 1\n getchar(); // take in following ~ (126), but discard code\n } else if(key==50) { // insert or F9-F12\n key = (int)getchar();\n if(key==126) { // insert\n key = 45;\n } else { // F9-F12\n key += 71; // 48, 49, 51, 52\n if(key<121) key++; // F11 and F12 are too low by 1\n getchar(); // take in following ~ (126), but discard code\n }\n } else if(key==51||key==53||key==54) { // delete, page up/down\n getchar(); // take in following ~ (126), but discard code\n }\n } else if(key==79) { // F1-F4\n key = 32+(int)getchar(); // 80-83\n }\n key = -key; // use negative numbers for escaped keys\n }\n term.c_lflag |= (ICANON|ECHO); // turn on line buffering and echoing\n tcsetattr(0, TCSANOW, &term);\n switch(key) {\n case 127: return 8; // backspace\n case -27: return 27; // escape\n case -51: return 127; // delete\n case -164: return 132; // \xc3\xa4\n case -182: return 148; // \xc3\xb6\n case -188: return 129; // \xc3\xbc\n case -132: return 142; // \xc3\x84\n case -150: return 153; // \xc3\x96\n case -156: return 154; // \xc3\x9c\n case -159: return 225; // \xc3\x9f\n case -181: return 230; // \xc2\xb5\n case -167: return 245; // \xc2\xa7\n case -176: return 248; // \xc2\xb0\n case -178: return 253; // \xc2\xb2\n case -179: return 252; // \xc2\xb3\n case -180: return 239; // \xc2\xb4\n case -65: return -38; // up arrow\n case -66: return -40; // down arrow\n case -68: return -37; // left arrow\n case -67: return -39; // right arrow\n case -53: return -33; // page up\n case -54: return -34; // page down\n case -72: return -36; // pos1\n case -70: return -35; // end\n case 0: continue;\n case 1: continue; // disable Ctrl + a\n case 2: continue; // disable Ctrl + b\n case 3: continue; // disable Ctrl + c (terminates program)\n case 4: continue; // disable Ctrl + d\n case 5: continue; // disable Ctrl + e\n case 6: continue; // disable Ctrl + f\n case 7: continue; // disable Ctrl + g\n case 8: continue; // disable Ctrl + h\n //case 9: continue; // disable Ctrl + i (ascii for tab)\n //case 10: continue; // disable Ctrl + j (ascii for new line)\n case 11: continue; // disable Ctrl + k\n case 12: continue; // disable Ctrl + l\n case 13: continue; // disable Ctrl + m\n case 14: continue; // disable Ctrl + n\n case 15: continue; // disable Ctrl + o\n case 16: continue; // disable Ctrl + p\n case 17: continue; // disable Ctrl + q\n case 18: continue; // disable Ctrl + r\n case 19: continue; // disable Ctrl + s\n case 20: continue; // disable Ctrl + t\n case 21: continue; // disable Ctrl + u\n case 22: continue; // disable Ctrl + v\n case 23: continue; // disable Ctrl + w\n case 24: continue; // disable Ctrl + x\n case 25: continue; // disable Ctrl + y\n case 26: continue; // disable Ctrl + z (terminates program)\n default: return key; // any other ASCII character\n }\n }\n}\n#endif // Windows/Linux\n最后，这是一个如何使用它的示例：
\nint main() {\n while(true) {\n const int key = key_press(); // blocks until a key is pressed\n println("Input is: "+to_string(key)+", \\""+(char)key+"\\"");\n }\n return 0;\n}\nncurses 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，但欢迎所有人！
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;
}
C和C++采用非常抽象的I/O视图,没有标准的方法来做你想做的事情.有标准方法可以从标准输入流中获取字符,如果有任何要获取的字符,则任何一种语言都没有定义任何其他内容.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,但是如果不知道你的目标环境是什么,就无法回答你的问题.
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