《Linux 程序设计入门》 第四版 §6.7 小键盘

小键盘

 

       小键盘中的字符要用字符串来表示，且不通的终端还有不通表示方法，识别起来要困难一些。Curses把它存储在terminfo中，curses.h定义了KEY_来表示逻辑键。

       序列到逻辑键转换的开启：

#include

int keypad(WINDOW *window_ptr, bool keypad_on);

         使用keypad模式的3个注意点：

❑转移序列有时间依赖性，注意网络影响。

❑ 注意按键适当的时间间隔

❑ 同样的多个键可能有不通功能。

 

# cat keypad.c

/*  Having initialized the program and the curses library, we set the Keypad mode TRUE.  */

 

#include

#include

#include

 

#define LOCAL_ESCAPE_KEY    27

 

int main()

{

    int key;

 

    initscr();

    crmode();

    keypad(stdscr, TRUE);

 

/*  Next, we must turn echo off

    to prevent the cursor being moved when some cursor keys are pressed.

    The screen is cleared and some text displayed.

    The program waits for each key stroke

    and, unless it's q, or produces an error, the key is printed.

    If the key strokes match one of the terminal's keypad sequences,

    then that sequence is printed instead.  */

 

    noecho();

 

    clear();

    mvprintw(5, 5, "Key pad demonstration. Press 'q' to quit");

    move(7, 5);

    refresh();

 

    key = getch();

    while(key != ERR && key != 'q') {

        move(7, 5);

        clrtoeol();

 

        if ((key >= 'A' && key <= 'Z') ||

            (key >= 'a' && key <= 'z')) {

            printw("Key was %c", (char)key);

        }

        else {

            switch(key) {

            case LOCAL_ESCAPE_KEY: printw("%s", "Escape key"); break;

            case KEY_END: printw("%s", "END key"); break;

            case KEY_BEG: printw("%s", "BEGINNING key"); break;

            case KEY_RIGHT: printw("%s", "RIGHT key"); break;

            case KEY_LEFT: printw("%s", "LEFT key"); break;

            case KEY_UP: printw("%s", "UP key"); break;

            case KEY_DOWN: printw("%s", "DOWN key"); break;

            default: printw("Unmatched - %d", key); break;

            } /* switch */

        } /* else */

 

        refresh();

        key = getch();

    } /* while */

 

    endwin();

    exit(EXIT_SUCCESS);

}