在Python中仅接受数字作为输入

Accepting only numbers as input in Python

有没有办法只接受Python中的数字，比如使用raw_input()？

我知道我总是可以获得输入并捕获ValueError异常，但我有兴趣知道是否有某些我可以强制提示只接受数字并冻结任何其他输入。

来自文档：

How do I get a single keypress at a time?

For Unix variants: There are several
solutions. It’s straightforward to do
this using curses, but curses is a
fairly large module to learn. Here’s a
solution without curses:

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import termios, fcntl, sys, os
fd = sys.stdin.fileno()

oldterm = termios.tcgetattr(fd)
newattr = termios.tcgetattr(fd)
newattr[3] = newattr[3] & ~termios.ICANON & ~termios.ECHO
termios.tcsetattr(fd, termios.TCSANOW, newattr)

oldflags = fcntl.fcntl(fd, fcntl.F_GETFL)
fcntl.fcntl(fd, fcntl.F_SETFL, oldflags | os.O_NONBLOCK)

try:
while 1:
try:
c = sys.stdin.read(1)
print"Got character", `c`
except IOError: pass
finally:
termios.tcsetattr(fd, termios.TCSAFLUSH, oldterm)
fcntl.fcntl(fd, fcntl.F_SETFL, oldflags)

You need the termios and the fcntl
module for any of this to work, and
I’ve only tried it on Linux, though it
should work elsewhere. In this code,
characters are read and printed one at
a time.

termios.tcsetattr() turns off stdin’s
echoing and disables canonical mode.
fcntl.fnctl() is used to obtain
stdin’s file descriptor flags and
modify them for non-blocking mode.
Since reading stdin when it is empty
results in an IOError, this error is
caught and ignored.

使用此功能，您可以抓取角色，检查它是否为数字，然后显示它。不过，我自己没试过。