如何让 Ruby 诅咒正确响应箭头键？

TL;DR

如何让 Ruby 诅咒正确响应箭头键？ KEY_UP 常量似乎与我的输入不匹配。

环境及问题描述

I am running Ruby 2.1.2 with the curses 1.0.1 gem https://github.com/ruby/curses. I'm trying to enable arrow-key navigation with curses. I've enabled Curses#getch http://www.ruby-doc.org/stdlib-2.0/libdoc/curses/rdoc/Curses.html#method-c-getch to fetch a single key without waiting for the carriage return by calling Curses#cbreak http://www.ruby-doc.org/stdlib-2.0/libdoc/curses/rdoc/Curses.html#method-c-cbreak, and this is working fine for the k character. However, I really want to enable arrow key navigation, and not just HJKL for movement.

目前，向上箭头在我的程序中打印 27，这似乎是正确的顺序值 http://www.ruby-doc.org/core-2.1.2/String.html#method-i-ord我的键盘给出了向上箭头键：

"^[[A".ord
#=> 27

and which should be matched by the Curses KEY_UP constant http://www.ruby-doc.org/stdlib-2.0/libdoc/curses/rdoc/Curses/Key.html. It isn't, and so falls through to the else statement to display the ordinal value. The up-arrow key also leaves [A as two separate characters at the command prompt when the ruby program exits, which might indicate that Curses#getch http://www.ruby-doc.org/stdlib-2.0/libdoc/curses/rdoc/Curses.html#method-c-getch isn't capturing the key press properly.

我的红宝石代码

require 'curses'
include  Curses

begin
  init_screen
  cbreak
  noecho
  keypad = true

  addstr 'Check for up arrow or letter k.'
  refresh
  ch = getch
  addch ?\n

  case ch
  when KEY_UP
    addstr "up arrow \n"
  when ?k
    addstr "up char \n"
  else
    addstr "%s\n" % ch
  end

  refresh
  sleep 1
ensure
  close_screen
end

在启用键盘的行中，您实际上创建了一个名为“keypad”的局部变量，因为该方法位于类中Curses::Window。 由于您没有制作自己的窗户（除了init_screen），你可以直接使用stdscr方法来参考标准的。如果我将第 8 行更改为：

stdscr.keypad = true

那么你的示例代码对我有用。