分享一个 Python 命令行下列表选择

可以通过上下键 + Enter 来选择，Ctrl+C 取消

[注意] 只能支持 linux + macos

超过 20 个数据，会出现 ==== ^ ==== 和 ==== v ==== 提示还有额外数据

# -*- coding: utf-8 -*- import sys import termios import tty left = u'\u001b[1000D' right = u'\u001b[1000C' clear_line = u'\u001b[2K' up = u'\u001b[1A' down = u'\u001b[1B' clear_to_bottom = u'\u001b[J' MAX_SHOW_COUNT = 20 class CommandSingleSelector: selectors = None cur_index = 0 cursor_index = -1 header_word = None is_cancel = False top_index = 0 bottom_index = 0 def __init__(self, selectors, header_word): self.selectors = selectors if len(selectors) > MAX_SHOW_COUNT: self.bottom_index = MAX_SHOW_COUNT else: self.bottom_index = len(selectors) - 1 self.header_word = header_word def up(self): if self.cur_index > 0: self.cur_index = self.cur_index - 1 if self.cur_index < self.top_index: self.top_index = self.top_index - 1 self.bottom_index = self.bottom_index - 1 self.print_multi_line() def down(self): if self.cur_index < len(self.selectors) - 1: self.cur_index = self.cur_index + 1 if self.cur_index > self.bottom_index: self.top_index = self.top_index + 1 self.bottom_index = self.bottom_index + 1 self.print_multi_line() def exit(self): self.clear_multi_line() def get_selector(self): sys.stdout.write(self.header_word + '\n') self.print_multi_line() is_multi_first = False is_multi_secOnd= False while True: fd = sys.stdin.fileno() old_settings = termios.tcgetattr(fd) try: tty.setraw(sys.stdin.fileno()) ch = sys.stdin.read(1) as_code = ord(ch) # find the multi key for up/down if as_code == 27: is_multi_first = True elif as_code == 91: if is_multi_first: is_multi_secOnd= True elif as_code == 65: if is_multi_first and is_multi_second: self.up() is_multi_secOnd= False is_multi_first = False elif as_code == 66: if is_multi_first and is_multi_second: self.down() is_multi_secOnd= False is_multi_first = False elif as_code == 13: is_multi_secOnd= False is_multi_first = False self.exit() break elif as_code == 3: is_multi_secOnd= False is_multi_first = False self.exit() self.is_cancel = True break else: is_multi_secOnd= False is_multi_first = False finally: termios.tcsetattr(fd, termios.TCSADRAIN, old_settings) if self.is_cancel: raise Exception('Cancel this operation.') return self.selectors[self.cur_index] def print_multi_line(self): sys.stdout.write((self.cursor_index + 1) * up + left) sys.stdout.write(clear_to_bottom) up_size = self.bottom_index - self.cur_index + 1 + 1 + 1 # first and last word has_first_sign = ' ' if self.top_index > 0: has_first_sign = ' ==== ^ ====' sys.stdout.write(left + clear_line + has_first_sign + '\n') for index, item in enumerate(self.selectors): if self.top_index <= index <= self.bottom_index: first_word = ' ' if index == self.cur_index: first_word = ' > ' sys.stdout.write(left + clear_line + first_word + item + '\n') else: sys.stdout.write(left + clear_line + first_word + item + '\n') has_last_sign = ' ' if len(self.selectors) - 1 > self.bottom_index: has_last_sign = ' ==== v ====' sys.stdout.write(left + clear_line + has_last_sign + '\n') back_to_cur_index = up * (up_size -1) self.cursor_index = self.cur_index - self.top_index sys.stdout.write(bck_to_cur_index) sys.stdout.write(left) def clear_multi_line(self): back_to_top = up * (self.cur_index - self.top_index + 2) sys.stdout.write(back_to_top) sys.stdout.write(left) sys.stdout.write(clear_to_bottom) if __name__ == '__main__': selectors = ['HP Printer', 'XiaoMi Printer','DELL Printer'] command_selector = CommandSingleSelector(selectors=selectors, header_word='Please Select One Printer: ') try: sel = command_selector.get_selector() print sel except Exception, e: print e.message