How to stop music if Enter key is pressed anytime the program is running?

问题

I want my program do something along the lines of:

while this program is running:
if the Enter key is pressed, stop the current music file playing.

Here is my code:

# https://docs.python.org/2/library/winsound.html

from msvcrt import getch
import winsound

while True:
    key = ord(getch())
    if key == 13:
        winsound.PlaySound(None, winsound.SND_NOWAIT)

winsound.PlaySound("SystemAsterisk", winsound.SND_ALIAS)
winsound.PlaySound("SystemExclamation", winsound.SND_ALIAS)
winsound.PlaySound("SystemExit", winsound.SND_ALIAS)
winsound.PlaySound("SystemHand", winsound.SND_ALIAS)
winsound.PlaySound("SystemQuestion", winsound.SND_ALIAS)

winsound.MessageBeep()

winsound.PlaySound('C:/Users/Admin/My Documents/tone.wav', winsound.SND_FILENAME)

winsound.PlaySound("SystemAsterisk", winsound.SND_ALIAS)

In the documentation (see link in the first line of my code), I am unsure weather winsound.SND_NOWAIT can be used like this: winsound.SND_NOWAIT(), or like how I tried to use it in my code under the if statement, or if both statements produce the same effect.

It is my understanding that the program will never get to play the sound files until after I press the Enter button, as the getch() part requires before continuing.

However, even if that part of the code does not care when I press anything, wouldn't the program get stuck in the while loop?

回答1:

The linked documentation for winsound.SND_NOWAIT states that:

Note: This flag is not supported on modern Windows platforms.

Besides that I don't think you understand how getch() works. Here's a link to its documentation:

https://msdn.microsoft.com/en-us/library/078sfkak

And here's another for a related one named kbhit() (which msvcrt also contains and I use below):

https://msdn.microsoft.com/en-us/library/58w7c94c.aspx

The following will stop the loop (and the program, since that's the only thing in it) when the Enter key is pressed. Note that it doesn't interrupt any single sound already playing because winsound doesn't provide a way to do that, but it will stop any further ones from being played.

from msvcrt import getch, kbhit
import winsound

class StopPlaying(Exception): pass # custom exception

def check_keyboard():
    while kbhit():
        ch = getch()
        if ch in '\x00\xe0':  # arrow or function key prefix?
            ch = getch()  # second call returns the actual key code
        if ord(ch) == 13:  # <Enter> key?
            raise StopPlaying

def play_sound(name, flags=winsound.SND_ALIAS):
    winsound.PlaySound(name, flags)
    check_keyboard()

try:
    while True:
        play_sound("SystemAsterisk")
        play_sound("SystemExclamation")
        play_sound("SystemExit")
        play_sound("SystemHand")
        play_sound("SystemQuestion")

        winsound.MessageBeep()

        play_sound('C:/Users/Admin/My Documents/tone.wav', winsound.SND_FILENAME)

        play_sound("SystemAsterisk")

except StopPlaying:
    print('Enter key pressed')

来源：https://stackoverflow.com/questions/45113705/how-to-stop-music-if-enter-key-is-pressed-anytime-the-program-is-running

标签

python

windows

python-2.7

audio

winsound