ChatGPT解决这个技术问题 Extra ChatGPT

如何从用户那里读取单个字符?

有没有办法从用户输入中读取一个字符?例如,他们在终端上按一个键并返回(有点像 getch())。我知道 Windows 中有一个功能,但我想要跨平台的东西。

在 Windows 上,我遇到了与此 question 相同的问题。解决方案是按照那里的建议将 msvcrt.getch 替换为 msvcrt.getwch
解决方案是安装 getch 模块“pip install getch”。对于 Python2,使用命令“pip2 install files.pythonhosted.org/packages/56/f7/…”。此解决方案也适用于 Termux (Android)。
最简单的解决方案是使用 sshkeyboard。它比 getch 需要更少的编码,而且它是一个跨平台的解决方案。
我无法相信所有这些复杂的答案。在 Ruby 中:input = STDIN.getch 就是这样。
@user93883 NameError: global name 'STDIN' is not defined 。也许它毕竟不是那么简单。

m
martineau

这是 ActiveState Recipes 站点的链接,该站点说明了如何在 Windows、Linux 和 OSX 中读取单个字符:

    getch()-like unbuffered character reading from stdin on both Windows and Unix

class _Getch:
    """Gets a single character from standard input.  Does not echo to the
screen."""
    def __init__(self):
        try:
            self.impl = _GetchWindows()
        except ImportError:
            self.impl = _GetchUnix()

    def __call__(self): return self.impl()


class _GetchUnix:
    def __init__(self):
        import tty, sys

    def __call__(self):
        import sys, tty, termios
        fd = sys.stdin.fileno()
        old_settings = termios.tcgetattr(fd)
        try:
            tty.setraw(sys.stdin.fileno())
            ch = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
        return ch


class _GetchWindows:
    def __init__(self):
        import msvcrt

    def __call__(self):
        import msvcrt
        return msvcrt.getch()


getch = _Getch()

代码似乎足够短,您可以只包含它,但是 +1 可以这么快地找到一个好的(跨平台)答案。
它是否能很好地处理非拉丁文(例如西里尔文)字母?我有一个问题,无法弄清楚,如果这是我的错误,或者不是。
我不喜欢像某种 if 语句那样使用 ImportError 异常;为什么不调用 platform.system() 来检查操作系统?
@Seismoid:通常认为请求宽恕更好,请参阅stackoverflow.com/questions/12265451/…
不适用于 OS X:“old_settings = termios.tcgetattr(fd)”“termios.error: (25, 'Inappropriate ioctl for device')”
m
mgilson
sys.stdin.read(1)

基本上会从 STDIN 读取 1 个字节。

如果您必须使用不等待 \n 的方法,您可以按照上一个答案中的建议使用此代码:

class _Getch:
    """Gets a single character from standard input.  Does not echo to the screen."""
    def __init__(self):
        try:
            self.impl = _GetchWindows()
        except ImportError:
            self.impl = _GetchUnix()

    def __call__(self): return self.impl()


class _GetchUnix:
    def __init__(self):
        import tty, sys

    def __call__(self):
        import sys, tty, termios
        fd = sys.stdin.fileno()
        old_settings = termios.tcgetattr(fd)
        try:
            tty.setraw(sys.stdin.fileno())
            ch = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
        return ch


class _GetchWindows:
    def __init__(self):
        import msvcrt

    def __call__(self):
        import msvcrt
        return msvcrt.getch()


getch = _Getch()

取自 http://code.activestate.com/recipes/134892/


我觉得 sys.stdin.read(1) 等待 \n 很奇怪,哈哈。不过,感谢您的提交。
一个字符还是一个字节?那不一样。
@Evan,那是因为 python 默认处于行缓冲模式
@EvanFosmark:sys.stdin.read(1) 不一定要等待\ n,而是决定何时将其他字符发送到您的程序的终端程序在看到'\ n'之前不会写入它们-否则会如何您可以按退格键并更正您输入的内容吗? (对此的严肃回答是 - 教 python 程序实现行控制,保留缓冲区,处理退格,但这是一个不同的世界,当你只是“读取一个字符”时,你可能不想购买,并且可以让你的行处理与系统上的所有其他程序不同。)
@Seismoid EAFP
L
Louis

两个答案中逐字引用的 ActiveState recipe 是过度设计的。可以归结为:

def _find_getch():
    try:
        import termios
    except ImportError:
        # Non-POSIX. Return msvcrt's (Windows') getch.
        import msvcrt
        return msvcrt.getch

    # POSIX system. Create and return a getch that manipulates the tty.
    import sys, tty
    def _getch():
        fd = sys.stdin.fileno()
        old_settings = termios.tcgetattr(fd)
        try:
            tty.setraw(fd)
            ch = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
        return ch

    return _getch

getch = _find_getch()

好的。但这也会读取 KeyboardInterrupt (Ctrl+C) 的第一个字符,并且代码有可能以 0 退出。
S
Søren Løvborg

同样值得尝试的是 readchar 库,它部分基于其他答案中提到的 ActiveState 配方。

安装:

pip install readchar

用法:

import readchar
print("Reading a char:")
print(repr(readchar.readchar()))
print("Reading a key:")
print(repr(readchar.readkey()))

使用 Python 2.7 在 Windows 和 Linux 上测试。

在 Windows 上,仅支持映射到字母或 ASCII 控制代码的键(Backspace、Enter、Esc、Tab、Ctrl+字母)。在 GNU/Linux 上(可能取决于确切的终端?)您还可以获得 Insert、Delete、Pg Up、Pg Dn、Home、End 和 F n 键……但是,将这些特殊键与 Esc 分开存在问题。

警告:与此处的大多数(全部?)答案一样,信号键如 Ctrl+CCtrl+DCtrl+Z 被捕获并返回(分别为 '\x03''\x04''\x1a');您的程序可能很难中止。


也适用于 Linux 上的 Python 3。比 getch 好得多,因为 readchar 允许在等待密钥时打印到标准输出(通过线程或异步)。
在 Win10 + Python 3.5 上测试: ERROR:root:'in ' 需要字符串作为左操作数,而不是字节 Traceback(最近一次调用最后一次):文件“..\main.py”,第 184 行,在包装器结果 = func(*args, **kwargs) 文件“C:\GitHub\Python-Demo\demo\day_hello.py”,第 41 行,在 readch_eg print(readchar.readchar()) 文件“C:\Users\ipcjs\AppData \Local\Programs\Python\Python35\lib\site-packages\readchar\readchar_windows.py",第 14 行,在 readchar 中,而 ch in '\x00\xe0': TypeError: 'in ' 需要字符串作为左操作数,而不是字节
@ipcjs 请将该错误报告给维护者
这是最好的答案。仅为此功能添加对 VS C++ 库的依赖项是疯狂的。
有关为 Control+... 或退格等返回的序列的完整列表,您可以查看此处:github.com/magmax/python-readchar/blob/master/readchar/key.py
j
jdi

另一种方法:

import os
import sys    
import termios
import fcntl

def getch():
  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)
        break
      except IOError: pass
  finally:
    termios.tcsetattr(fd, termios.TCSAFLUSH, oldterm)
    fcntl.fcntl(fd, fcntl.F_SETFL, oldflags)
  return c

this blog post


似乎对我不起作用 - 调用时立即返回空字符串。在带有 Python 3.6 的 Linux 上。
@Marein 如果您希望它阻止(等待输入),请删除 | os.O_NONBLOCK。否则,你可以把它放在一个循环中(最好在循环中睡一会儿以防止旋转)。
在 Python 中,使用 while True 比使用 while 1 更好。
l
lucid_dreamer

(当前)排名靠前的答案(使用 ActiveState 代码)过于复杂。当仅仅一个函数就足够时,我看不到使用类的理由。下面是两个实现相同的功能但代码更易读的实现。

这两种实现:

在 Python 2 或 Python 3 中工作得很好 在 Windows、OSX 和 Linux 上工作 只读取一个字节(即它们不等待换行符)不依赖任何外部库是自包含的(没有代码之外的函数定义)

版本 1:可读且简单

def getChar():
    try:
        # for Windows-based systems
        import msvcrt # If successful, we are on Windows
        return msvcrt.getch()

    except ImportError:
        # for POSIX-based systems (with termios & tty support)
        import tty, sys, termios  # raises ImportError if unsupported

        fd = sys.stdin.fileno()
        oldSettings = termios.tcgetattr(fd)

        try:
            tty.setcbreak(fd)
            answer = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, oldSettings)

        return answer

版本 2:避免重复导入和异常处理:

[编辑] 我错过了 ActiveState 代码的一个优势。如果您计划多次读取字符,则该代码避免了在类 Unix 系统上重复 Windows 导入和 ImportError 异常处理的(可忽略的)成本。虽然您可能应该更关心代码的可读性而不是微不足道的优化,但这里有一个替代方法(它类似于 Louis 的答案,但 getChar() 是自包含的),其功能与 ActiveState 代码相同并且更具可读性:

def getChar():
    # figure out which function to use once, and store it in _func
    if "_func" not in getChar.__dict__:
        try:
            # for Windows-based systems
            import msvcrt # If successful, we are on Windows
            getChar._func=msvcrt.getch

        except ImportError:
            # for POSIX-based systems (with termios & tty support)
            import tty, sys, termios # raises ImportError if unsupported

            def _ttyRead():
                fd = sys.stdin.fileno()
                oldSettings = termios.tcgetattr(fd)

                try:
                    tty.setcbreak(fd)
                    answer = sys.stdin.read(1)
                finally:
                    termios.tcsetattr(fd, termios.TCSADRAIN, oldSettings)

                return answer

            getChar._func=_ttyRead

    return getChar._func()

执行上述任一 getChar() 版本的示例代码:

from __future__ import print_function # put at top of file if using Python 2

# Example of a prompt for one character of input
promptStr   = "Please give me a character:"
responseStr = "Thank you for giving me a '{}'."
print(promptStr, end="\n> ")
answer = getChar()
print("\n")
print(responseStr.format(answer))

在打印消息同时等待密钥(多线程)时,我遇到了 tty.setraw() 的问题。长话短说,我发现使用 tty.setcbreak() 可以让你在不破坏所有其他正常内容的情况下获得单个角色。 answer中的长篇故事
我在使用 PyCharm 执行 shell 模拟器时遇到了以下错误:... old_settings = termios.tcgetattr(fd) ... termios.error: (25, 'Inappropriate ioctl for device')
This answer 早于您的方法,是一种更好的方法。
k
kiri

此代码基于 here,如果 Ctrl+CCtrl+D 被按下。

应该在 Windows 和 Linux 上工作。 OS X 版本可从原始来源获得。

class _Getch:
    """Gets a single character from standard input.  Does not echo to the screen."""
    def __init__(self):
        try:
            self.impl = _GetchWindows()
        except ImportError:
            self.impl = _GetchUnix()

    def __call__(self): 
        char = self.impl()
        if char == '\x03':
            raise KeyboardInterrupt
        elif char == '\x04':
            raise EOFError
        return char

class _GetchUnix:
    def __init__(self):
        import tty
        import sys

    def __call__(self):
        import sys
        import tty
        import termios
        fd = sys.stdin.fileno()
        old_settings = termios.tcgetattr(fd)
        try:
            tty.setraw(sys.stdin.fileno())
            ch = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
        return ch


class _GetchWindows:
    def __init__(self):
        import msvcrt

    def __call__(self):
        import msvcrt
        return msvcrt.getch()


getch = _Getch()

它支持 ASCII 以外的 Unicode(这是其他一些解决方案所关心的问题)(它适用于 linux)
N
NinjaFart

尝试使用这个:http://home.wlu.edu/~levys/software/kbhit.py 它是非阻塞的(这意味着您可以有一个 while 循环并在不停止它的情况下检测按键)并且是跨平台的。

import os

# Windows
if os.name == 'nt':
    import msvcrt

# Posix (Linux, OS X)
else:
    import sys
    import termios
    import atexit
    from select import select


class KBHit:

    def __init__(self):
        '''Creates a KBHit object that you can call to do various keyboard things.'''

        if os.name == 'nt':
            pass

        else:

            # Save the terminal settings
            self.fd = sys.stdin.fileno()
            self.new_term = termios.tcgetattr(self.fd)
            self.old_term = termios.tcgetattr(self.fd)

            # New terminal setting unbuffered
            self.new_term[3] = (self.new_term[3] & ~termios.ICANON & ~termios.ECHO)
            termios.tcsetattr(self.fd, termios.TCSAFLUSH, self.new_term)

            # Support normal-terminal reset at exit
            atexit.register(self.set_normal_term)


    def set_normal_term(self):
        ''' Resets to normal terminal.  On Windows this is a no-op.
        '''

        if os.name == 'nt':
            pass

        else:
            termios.tcsetattr(self.fd, termios.TCSAFLUSH, self.old_term)


    def getch(self):
        ''' Returns a keyboard character after kbhit() has been called.
            Should not be called in the same program as getarrow().
        '''

        s = ''

        if os.name == 'nt':
            return msvcrt.getch().decode('utf-8')

        else:
            return sys.stdin.read(1)


    def getarrow(self):
        ''' Returns an arrow-key code after kbhit() has been called. Codes are
        0 : up
        1 : right
        2 : down
        3 : left
        Should not be called in the same program as getch().
        '''

        if os.name == 'nt':
            msvcrt.getch() # skip 0xE0
            c = msvcrt.getch()
            vals = [72, 77, 80, 75]

        else:
            c = sys.stdin.read(3)[2]
            vals = [65, 67, 66, 68]

        return vals.index(ord(c.decode('utf-8')))


    def kbhit(self):
        ''' Returns True if keyboard character was hit, False otherwise.
        '''
        if os.name == 'nt':
            return msvcrt.kbhit()

        else:
            dr,dw,de = select([sys.stdin], [], [], 0)
            return dr != []

一个使用这个的例子:

import kbhit

kb = kbhit.KBHit()

while(True): 
    print("Key not pressed") #Do something
    if kb.kbhit(): #If a key is pressed:
        k_in = kb.getch() #Detect what key was pressed
        print("You pressed ", k_in, "!") #Do something
kb.set_normal_term()

或者您可以使用 getch module from PyPi。但这会阻塞while循环


尽管这远远低于解决方案的优先顺序,但它是唯一一个在 MacOS 上没有弄乱我的标准输出的解决方案 - 谢谢!
H
HoldOffHunger

答案 here 提供了丰富的信息,但是我还想要一种方法来异步获取按键并在单独的事件中触发按键,所有这些都以线程安全、跨平台的方式。 PyGame 对我来说也太臃肿了。所以我做了以下(在 Python 2.7 中,但我怀疑它很容易移植),我想我会在这里分享,以防它对其他人有用。我将它存储在一个名为 keyPress.py 的文件中。

class _Getch:
    """Gets a single character from standard input.  Does not echo to the
screen. From http://code.activestate.com/recipes/134892/"""
    def __init__(self):
        try:
            self.impl = _GetchWindows()
        except ImportError:
            try:
                self.impl = _GetchMacCarbon()
            except(AttributeError, ImportError):
                self.impl = _GetchUnix()

    def __call__(self): return self.impl()


class _GetchUnix:
    def __init__(self):
        import tty, sys, termios # import termios now or else you'll get the Unix version on the Mac

    def __call__(self):
        import sys, tty, termios
        fd = sys.stdin.fileno()
        old_settings = termios.tcgetattr(fd)
        try:
            tty.setraw(sys.stdin.fileno())
            ch = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
        return ch

class _GetchWindows:
    def __init__(self):
        import msvcrt

    def __call__(self):
        import msvcrt
        return msvcrt.getch()

class _GetchMacCarbon:
    """
    A function which returns the current ASCII key that is down;
    if no ASCII key is down, the null string is returned.  The
    page http://www.mactech.com/macintosh-c/chap02-1.html was
    very helpful in figuring out how to do this.
    """
    def __init__(self):
        import Carbon
        Carbon.Evt #see if it has this (in Unix, it doesn't)

    def __call__(self):
        import Carbon
        if Carbon.Evt.EventAvail(0x0008)[0]==0: # 0x0008 is the keyDownMask
            return ''
        else:
            #
            # The event contains the following info:
            # (what,msg,when,where,mod)=Carbon.Evt.GetNextEvent(0x0008)[1]
            #
            # The message (msg) contains the ASCII char which is
            # extracted with the 0x000000FF charCodeMask; this
            # number is converted to an ASCII character with chr() and
            # returned
            #
            (what,msg,when,where,mod)=Carbon.Evt.GetNextEvent(0x0008)[1]
            return chr(msg & 0x000000FF)

import threading
            
            
# From  https://stackoverflow.com/a/2022629/2924421
class Event(list):
    def __call__(self, *args, **kwargs):
        for f in self:
            f(*args, **kwargs)

    def __repr__(self):
        return "Event(%s)" % list.__repr__(self)            


def getKey():
    inkey = _Getch()
    import sys
    for i in xrange(sys.maxint):
        k=inkey()
        if k<>'':break
    return k

class KeyCallbackFunction():
    callbackParam = None
    actualFunction = None
    
    def __init__(self, actualFunction, callbackParam):
        self.actualFunction = actualFunction
        self.callbackParam = callbackParam

    def doCallback(self, inputKey):
        if not self.actualFunction is None:
            if self.callbackParam is None:
                callbackFunctionThread = threading.Thread(target=self.actualFunction, args=(inputKey,))
            else:
                callbackFunctionThread = threading.Thread(target=self.actualFunction, args=(inputKey,self.callbackParam))
            
            callbackFunctionThread.daemon = True
            callbackFunctionThread.start()
        
        

class KeyCapture():


    gotKeyLock = threading.Lock()
    gotKeys = []
    gotKeyEvent = threading.Event()

    keyBlockingSetKeyLock = threading.Lock()

    addingEventsLock = threading.Lock()
    keyReceiveEvents = Event()


    keysGotLock = threading.Lock()
    keysGot = []

    keyBlockingKeyLockLossy = threading.Lock()
    keyBlockingKeyLossy = None
    keyBlockingEventLossy = threading.Event()
    
    keysBlockingGotLock = threading.Lock()
    keysBlockingGot = []
    keyBlockingGotEvent = threading.Event()
    

    
    wantToStopLock = threading.Lock()
    wantToStop = False
    
    stoppedLock = threading.Lock()
    stopped = True
    
    isRunningEvent = False
    
    getKeyThread = None
    
    keyFunction = None
    keyArgs = None
    
    # Begin capturing keys. A seperate thread is launched that
    # captures key presses, and then these can be received via get,
    # getAsync, and adding an event via addEvent. Note that this
    # will prevent the system to accept keys as normal (say, if
    # you are in a python shell) because it overrides that key
    # capturing behavior.
    
    # If you start capture when it's already been started, a
    # InterruptedError("Keys are still being captured")
    # will be thrown
    
    # Note that get(), getAsync() and events are independent, so if a key is pressed:
    #
    # 1: Any calls to get() that are waiting, with lossy on, will return
    #    that key
    # 2: It will be stored in the queue of get keys, so that get() with lossy
    #    off will return the oldest key pressed not returned by get() yet.
    # 3: All events will be fired with that key as their input
    # 4: It will be stored in the list of getAsync() keys, where that list
    #    will be returned and set to empty list on the next call to getAsync().
    # get() call with it, aand add it to the getAsync() list.
    def startCapture(self, keyFunction=None, args=None):
        # Make sure we aren't already capturing keys
        self.stoppedLock.acquire()
        if not self.stopped:
            self.stoppedLock.release()
            raise InterruptedError("Keys are still being captured")
            return
        self.stopped = False
        self.stoppedLock.release()
        
        # If we have captured before, we need to allow the get() calls to actually
        # wait for key presses now by clearing the event
        if self.keyBlockingEventLossy.is_set():
            self.keyBlockingEventLossy.clear()
            
        # Have one function that we call every time a key is captured, intended for stopping capture
        # as desired
        self.keyFunction = keyFunction
        self.keyArgs = args
        
        # Begin capturing keys (in a seperate thread)
        self.getKeyThread = threading.Thread(target=self._threadProcessKeyPresses)
        self.getKeyThread.daemon = True
        self.getKeyThread.start()
        
        # Process key captures (in a seperate thread)
        self.getKeyThread = threading.Thread(target=self._threadStoreKeyPresses)
        self.getKeyThread.daemon = True
        self.getKeyThread.start()
    
    
    def capturing(self):
        self.stoppedLock.acquire()
        isCapturing = not self.stopped
        self.stoppedLock.release()
        return isCapturing
    # Stops the thread that is capturing keys on the first opporunity
    # has to do so. It usually can't stop immediately because getting a key
    # is a blocking process, so this will probably stop capturing after the
    # next key is pressed.
    #
    # However, Sometimes if you call stopCapture it will stop before starting capturing the
    # next key, due to multithreading race conditions. So if you want to stop capturing
    # reliably, call stopCapture in a function added via addEvent. Then you are
    # guaranteed that capturing will stop immediately after the rest of the callback
    # functions are called (before starting to capture the next key).
    def stopCapture(self):
        self.wantToStopLock.acquire()
        self.wantToStop = True 
        self.wantToStopLock.release()

    # Takes in a function that will be called every time a key is pressed (with that
    # key passed in as the first paramater in that function)
    def addEvent(self, keyPressEventFunction, args=None):   
        self.addingEventsLock.acquire()
        callbackHolder = KeyCallbackFunction(keyPressEventFunction, args)
        self.keyReceiveEvents.append(callbackHolder.doCallback)
        self.addingEventsLock.release()
    def clearEvents(self):
        self.addingEventsLock.acquire()
        self.keyReceiveEvents = Event()
        self.addingEventsLock.release()
    # Gets a key captured by this KeyCapture, blocking until a key is pressed.
    # There is an optional lossy paramater:
    # If True all keys before this call are ignored, and the next pressed key
    #   will be returned.
    # If False this will return the oldest key captured that hasn't
    #   been returned by get yet. False is the default.
    def get(self, lossy=False):
        if lossy:
            # Wait for the next key to be pressed
            self.keyBlockingEventLossy.wait()
            self.keyBlockingKeyLockLossy.acquire()
            keyReceived = self.keyBlockingKeyLossy
            self.keyBlockingKeyLockLossy.release()
            return keyReceived
        else:
            while True:
                # Wait until a key is pressed
                self.keyBlockingGotEvent.wait()
                
                # Get the key pressed
                readKey = None
                self.keysBlockingGotLock.acquire()
                # Get a key if it exists
                if len(self.keysBlockingGot) != 0:
                    readKey = self.keysBlockingGot.pop(0)
                # If we got the last one, tell us to wait
                if len(self.keysBlockingGot) == 0:
                    self.keyBlockingGotEvent.clear()
                self.keysBlockingGotLock.release()
                
                # Process the key (if it actually exists)
                if not readKey is None:
                    return readKey
                
                # Exit if we are stopping
                self.wantToStopLock.acquire()
                if self.wantToStop:
                    self.wantToStopLock.release()
                    return None
                self.wantToStopLock.release()
            
            
            
    
    def clearGetList(self):
        self.keysBlockingGotLock.acquire()
        self.keysBlockingGot = []
        self.keysBlockingGotLock.release()
    
    # Gets a list of all keys pressed since the last call to getAsync, in order
    # from first pressed, second pressed, .., most recent pressed
    def getAsync(self):
        self.keysGotLock.acquire();
        keysPressedList = list(self.keysGot)
        self.keysGot = []
        self.keysGotLock.release()
        return keysPressedList
    
    def clearAsyncList(self):
        self.keysGotLock.acquire();
        self.keysGot = []
        self.keysGotLock.release();

    def _processKey(self, readKey):
        # Append to list for GetKeyAsync
        self.keysGotLock.acquire()
        self.keysGot.append(readKey)
        self.keysGotLock.release()
        
        # Call lossy blocking key events
        self.keyBlockingKeyLockLossy.acquire()
        self.keyBlockingKeyLossy = readKey
        self.keyBlockingEventLossy.set()
        self.keyBlockingEventLossy.clear()
        self.keyBlockingKeyLockLossy.release()
        
        # Call non-lossy blocking key events
        self.keysBlockingGotLock.acquire()
        self.keysBlockingGot.append(readKey)
        if len(self.keysBlockingGot) == 1:
            self.keyBlockingGotEvent.set()
        self.keysBlockingGotLock.release()
        
        # Call events added by AddEvent
        self.addingEventsLock.acquire()
        self.keyReceiveEvents(readKey)
        self.addingEventsLock.release()

    def _threadProcessKeyPresses(self):
        while True:
            # Wait until a key is pressed
            self.gotKeyEvent.wait()
            
            # Get the key pressed
            readKey = None
            self.gotKeyLock.acquire()
            # Get a key if it exists
            if len(self.gotKeys) != 0:
                readKey = self.gotKeys.pop(0)
            # If we got the last one, tell us to wait
            if len(self.gotKeys) == 0:
                self.gotKeyEvent.clear()
            self.gotKeyLock.release()
            
            # Process the key (if it actually exists)
            if not readKey is None:
                self._processKey(readKey)
            
            # Exit if we are stopping
            self.wantToStopLock.acquire()
            if self.wantToStop:
                self.wantToStopLock.release()
                break
            self.wantToStopLock.release()
            
    def _threadStoreKeyPresses(self):
        while True:
            # Get a key
            readKey = getKey()
            
            # Run the potential shut down function
            if not self.keyFunction is None:
                self.keyFunction(readKey, self.keyArgs)
        
            # Add the key to the list of pressed keys
            self.gotKeyLock.acquire()
            self.gotKeys.append(readKey)
            if len(self.gotKeys) == 1:
                self.gotKeyEvent.set()
            self.gotKeyLock.release()
            
            # Exit if we are stopping
            self.wantToStopLock.acquire()
            if self.wantToStop:
                self.wantToStopLock.release()
                self.gotKeyEvent.set()
                break
            self.wantToStopLock.release()
    
        
        # If we have reached here we stopped capturing
        
        # All we need to do to clean up is ensure that
        # all the calls to .get() now return None.
        # To ensure no calls are stuck never returning,
        # we will leave the event set so any tasks waiting
        # for it immediately exit. This will be unset upon
        # starting key capturing again.
        
        self.stoppedLock.acquire()
        
        # We also need to set this to True so we can start up
        # capturing again.
        self.stopped = True
        self.stopped = True
        
        self.keyBlockingKeyLockLossy.acquire()
        self.keyBlockingKeyLossy = None
        self.keyBlockingEventLossy.set()
        self.keyBlockingKeyLockLossy.release()
        
        self.keysBlockingGotLock.acquire()
        self.keyBlockingGotEvent.set()
        self.keysBlockingGotLock.release()
        
        self.stoppedLock.release()

这个想法是,您可以简单地调用 keyPress.getKey(),它将从键盘读取一个键,然后返回它。

如果您想要更多的东西,我制作了一个 KeyCapture 对象。您可以通过 keys = keyPress.KeyCapture() 之类的方式创建一个。

然后你可以做三件事:

addEvent(functionName) 接受任何接受一个参数的函数。然后每次按下一个键时,都会调用这个函数,并在输入时使用该键的字符串。这些在单独的线程中运行,因此您可以阻止所有您想要的,它不会弄乱 KeyCapturer 的功能,也不会延迟其他事件。

get() 以与以前相同的阻塞方式返回一个键。现在在这里需要它,因为现在通过 KeyCapture 对象捕获键,因此 keyPress.getKey() 会与该行为冲突,并且它们都会丢失一些键,因为一次只能捕获一个键。另外,假设用户按“a”,然后按“b”,您调用 get(),用户按“c”。该 get() 调用将立即返回“a”,然后如果您再次调用它,它将返回“b”,然后是“c”。如果再次调用它,它将阻塞,直到按下另一个键。这样可以确保您不会错过任何键,如果需要,可以采用阻塞方式。所以这种方式和之前的keyPress.getKey()有点不同

如果您希望返回 getKey() 的行为,get(lossy=True)get() 类似,只是它只返回在调用 get() 之后按下的键。所以在上面的例子中,get() 会阻塞直到用户按下'c',然后如果你再次调用它,它会阻塞直到按下另一个键。

getAsync() 有点不同。它是为进行大量处理而设计的,然后偶尔会返回并检查按下了哪些键。因此,getAsync() 返回自上次调用 getAsync() 以来按下的所有键的列表,按从最早按下的键到最近按下的键的顺序排列。它也不会阻塞,这意味着如果自上次调用 getAsync() 以来没有按下任何键,则将返回一个空的 []

要真正开始捕获键,您需要使用上面创建的 keys 对象调用 keys.startCapture()startCapture 是非阻塞的,它只是启动一个只记录按键的线程,并启动另一个线程来处理这些按键。有两个线程来确保记录按键的线程不会错过任何键。

如果您想停止捕获键,您可以调用 keys.stopCapture(),它会停止捕获键。但是,由于捕获键是一种阻塞操作,因此捕获键的线程可能会在调用 stopCapture() 之后再捕获一个键。

为了防止这种情况,您可以将一个可选参数传递给一个函数的 startCapture(functionName, args),该函数只是执行检查键是否等于“c”然后退出之类的操作。重要的是这个函数之前做的很少,例如,这里的睡眠会导致我们错过按键。

但是,如果在此函数中调用 stopCapture(),键捕获将立即停止,不再尝试捕获,并且所有 get() 调用将立即返回,如果尚未按下任何键,则返回 None。

此外,由于 get()getAsync() 存储所有先前按下的键(直到您检索它们),您可以调用 clearGetList()clearAsyncList() 来忘记先前按下的键。

请注意,get()getAsync() 和事件是独立的,因此如果按下某个键:

一个正在等待的 get() 调用,有损打开,将返回该密钥。其他等待呼叫(如果有)将继续等待。该键将存储在获取键的队列中,因此有损关闭的 get() 将返回 get() 尚未返回的最旧按下的键。所有事件都将使用该键作为其输入触发该键将存储在 getAsync() 键的列表中,该列表将被返回并在下次调用 getAsync() 时设置为空列表

如果这一切都太多了,这里有一个示例用例:

import keyPress
import time
import threading

def KeyPressed(k, printLock):
    printLock.acquire()
    print "Event: " + k
    printLock.release()
    time.sleep(4)
    printLock.acquire()
    print "Event after delay: " + k
    printLock.release()

def GetKeyBlocking(keys, printLock):    
    while keys.capturing():
        keyReceived = keys.get()
        time.sleep(1)
        printLock.acquire()
        if not keyReceived is None:
            print "Block " + keyReceived
        else:
            print "Block None"
        printLock.release()

def GetKeyBlockingLossy(keys, printLock):   
    while keys.capturing():
        keyReceived = keys.get(lossy=True)
        time.sleep(1)
        printLock.acquire()
        if not keyReceived is None:
            print "Lossy: " + keyReceived
        else:
            print "Lossy: None"
        printLock.release()

def CheckToClose(k, (keys, printLock)):
    printLock.acquire()
    print "Close: " + k
    printLock.release()
    if k == "c":
        keys.stopCapture()
        
printLock = threading.Lock()

print "Press a key:"
print "You pressed: " + keyPress.getKey()
print ""

keys = keyPress.KeyCapture()

keys.addEvent(KeyPressed, printLock)



print "Starting capture"
            
keys.startCapture(CheckToClose, (keys, printLock))
            
getKeyBlockingThread = threading.Thread(target=GetKeyBlocking, args=(keys, printLock))
getKeyBlockingThread.daemon = True
getKeyBlockingThread.start()

            
getKeyBlockingThreadLossy = threading.Thread(target=GetKeyBlockingLossy, args=(keys, printLock))
getKeyBlockingThreadLossy.daemon = True
getKeyBlockingThreadLossy.start()

while keys.capturing():
    keysPressed = keys.getAsync()
    printLock.acquire()
    if keysPressed != []:
        print "Async: " + str(keysPressed)
    printLock.release()
    time.sleep(1)

print "done capturing"

从我所做的简单测试来看,它对我来说效果很好,但如果我错过了一些东西,我也会很乐意接受其他人的反馈。

我也发布了这个here


T
ThP

这可能是上下文管理器的一个用例。抛开 Windows 操作系统的津贴,这是我的建议:

#!/usr/bin/env python3
# file: 'readchar.py'
"""
Implementation of a way to get a single character of input
without waiting for the user to hit <Enter>.
(OS is Linux, Ubuntu 14.04)
"""

import tty, sys, termios

class ReadChar():
    def __enter__(self):
        self.fd = sys.stdin.fileno()
        self.old_settings = termios.tcgetattr(self.fd)
        tty.setraw(sys.stdin.fileno())
        return sys.stdin.read(1)
    def __exit__(self, type, value, traceback):
        termios.tcsetattr(self.fd, termios.TCSADRAIN, self.old_settings)

def test():
    while True:
        with ReadChar() as rc:
            char = rc
        if ord(char) <= 32:
            print("You entered character with ordinal {}."\
                        .format(ord(char)))
        else:
            print("You entered character '{}'."\
                        .format(char))
        if char in "^C^D":
            sys.exit()

if __name__ == "__main__":
    test()

您还可以在 __enter__ 中返回 self 并使用返回 sys.stdin.read(1)read 方法,然后您可以在一个上下文中读取多个字符。
q
qel

如果我正在做一些复杂的事情,我会使用 curses 来读取密钥。但是很多时候我只想要一个简单的 Python 3 脚本,它使用标准库并且可以读取箭头键,所以我这样做:

import sys, termios, tty

key_Enter = 13
key_Esc = 27
key_Up = '\033[A'
key_Dn = '\033[B'
key_Rt = '\033[C'
key_Lt = '\033[D'

fdInput = sys.stdin.fileno()
termAttr = termios.tcgetattr(0)

def getch():
    tty.setraw(fdInput)
    ch = sys.stdin.buffer.raw.read(4).decode(sys.stdin.encoding)
    if len(ch) == 1:
        if ord(ch) < 32 or ord(ch) > 126:
            ch = ord(ch)
    elif ord(ch[0]) == 27:
        ch = '\033' + ch[1:]
    termios.tcsetattr(fdInput, termios.TCSADRAIN, termAttr)
    return ch

这正是我正在寻找的,简单的,并使用默认的 python 库,谢谢!!!
Y
Yash Rathi

您可以使用 click。它经过充分测试,可在 Linux、Mac 和视窗。

import click

print('Continue? [yn] ')
c = click.getchar()   # Gets a single character


if c == 'y':
    print('We will go on')
elif c == 'n':
    print('Abort!')
else:
    print('Invalid input :(')

D
Davoud Taghawi-Nejad

这是非阻塞的,读取一个键并将其存储在 keypress.key 中。

import Tkinter as tk


class Keypress:
    def __init__(self):
        self.root = tk.Tk()
        self.root.geometry('300x200')
        self.root.bind('<KeyPress>', self.onKeyPress)

    def onKeyPress(self, event):
        self.key = event.char

    def __eq__(self, other):
        return self.key == other

    def __str__(self):
        return self.key

在你的程序中

keypress = Keypress()

while something:
   do something
   if keypress == 'c':
        break
   elif keypress == 'i': 
       print('info')
   else:
       print("i dont understand %s" % keypress)

@ThorSummoner:这段代码有很多问题——所以不,它不适用于命令行应用程序。
鉴于 Windows 管理器正在运行,它为命令行应用程序运行。
不,它不能在无头操作系统中运行。但它确实在命令行窗口中运行。
i
ibic

ActiveState 的配方似乎包含一个“posix”系统的小错误,可防止 Ctrl-C 中断(我使用的是 Mac)。如果我将以下代码放入我的脚本中:

while(True):
    print(getch())

我将永远无法用 Ctrl-C 终止脚本,我必须杀死我的终端才能逃脱。

我相信下面这行是原因,也太残酷了:

tty.setraw(sys.stdin.fileno())

除此之外,包 tty 并不是真正需要的,termios 足以处理它。

下面是对我有用的改进代码(Ctrl-C 将中断),额外的 getche 函数会在您键入时回显字符:

if sys.platform == 'win32':
    import msvcrt
    getch = msvcrt.getch
    getche = msvcrt.getche
else:
    import sys
    import termios
    def __gen_ch_getter(echo):
        def __fun():
            fd = sys.stdin.fileno()
            oldattr = termios.tcgetattr(fd)
            newattr = oldattr[:]
            try:
                if echo:
                    # disable ctrl character printing, otherwise, backspace will be printed as "^?"
                    lflag = ~(termios.ICANON | termios.ECHOCTL)
                else:
                    lflag = ~(termios.ICANON | termios.ECHO)
                newattr[3] &= lflag
                termios.tcsetattr(fd, termios.TCSADRAIN, newattr)
                ch = sys.stdin.read(1)
                if echo and ord(ch) == 127: # backspace
                    # emulate backspace erasing
                    # https://stackoverflow.com/a/47962872/404271
                    sys.stdout.write('\b \b')
            finally:
                termios.tcsetattr(fd, termios.TCSADRAIN, oldattr)
            return ch
        return __fun
    getch = __gen_ch_getter(False)
    getche = __gen_ch_getter(True)

参考:

https://pypi.python.org/pypi/getch


H
Hackaholic

用 pygame 试试这个:

import pygame
pygame.init()             // eliminate error, pygame.error: video system not initialized
keys = pygame.key.get_pressed()

if keys[pygame.K_SPACE]:
    d = "space key"

print "You pressed the", d, "."

这是个好主意,但在命令行上不起作用:pygame.error: video system not initialized
N
Noah

其他答案之一中的评论提到了 cbreak 模式,这对于 Unix 实现很重要,因为您通常不希望 ^C (KeyboardError) 被 getchar 使用(就像将终端设置为原始模式时一样,正如大多数其他答案所做的那样)。

另一个重要的细节是,如果你想读取一个字符而不是一个字节,你应该从输入流中读取 4 个字节,因为这是 UTF-8 中单个字符包含的最大字节数(Python 3+ )。对于多字节字符(如键盘箭头),只读取一个字节会产生意想不到的结果。

这是我为 Unix 更改的实现:

import contextlib
import os
import sys
import termios
import tty


_MAX_CHARACTER_BYTE_LENGTH = 4


@contextlib.contextmanager
def _tty_reset(file_descriptor):
    """
    A context manager that saves the tty flags of a file descriptor upon
    entering and restores them upon exiting.
    """
    old_settings = termios.tcgetattr(file_descriptor)
    try:
        yield
    finally:
        termios.tcsetattr(file_descriptor, termios.TCSADRAIN, old_settings)


def get_character(file=sys.stdin):
    """
    Read a single character from the given input stream (defaults to sys.stdin).
    """
    file_descriptor = file.fileno()
    with _tty_reset(file_descriptor):
        tty.setcbreak(file_descriptor)
        return os.read(file_descriptor, _MAX_CHARACTER_BYTE_LENGTH)

J
John Mark

python 中的 curses 包可用于从终端输入“原始”模式,只需几条语句。 Curses的主要用途是接管屏幕进行输出,这可能不是你想要的。此代码段使用 print() 语句代替,这些语句可用,但您必须了解 curses 如何更改附加到输出的行尾。

#!/usr/bin/python3
# Demo of single char terminal input in raw mode with the curses package.
import sys, curses

def run_one_char(dummy):
    'Run until a carriage return is entered'
    char = ' '
    print('Welcome to curses', flush=True)
    while ord(char) != 13:
        char = one_char()

def one_char():
    'Read one character from the keyboard'
    print('\r? ', flush= True, end = '')

    ## A blocking single char read in raw mode. 
    char = sys.stdin.read(1)
    print('You entered %s\r' % char)
    return char

## Must init curses before calling any functions
curses.initscr()
## To make sure the terminal returns to its initial settings,
## and to set raw mode and guarantee cleanup on exit. 
curses.wrapper(run_one_char)
print('Curses be gone!')

t
theAlse

我相信这是最优雅的解决方案之一。

import os

if os.name == 'nt':
    import msvcrt
    def getch():
        return msvcrt.getch().decode()
else:
    import sys, tty, termios
    fd = sys.stdin.fileno()
    old_settings = termios.tcgetattr(fd)
    def getch():
        try:
            tty.setraw(sys.stdin.fileno())
            ch = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
        return ch

然后在代码中使用它:

if getch() == chr(ESC_ASCII_VALUE):
    print("ESC!")

i
ilon

最简单的跨平台解决方案是 sshkeyboard。使用 pip install sshkeyboard 安装,

然后编写脚本,例如:

from sshkeyboard import listen_keyboard

def press(key):
    print(f"'{key}' pressed")

def release(key):
    print(f"'{key}' released")

listen_keyboard(
    on_press=press,
    on_release=release,
)

它会打印:

'a' pressed
'a' released

按下 A 键时。 ESC 键默认结束监听。

与curses、tkinter 和getch 相比,它需要更少的编码。


M
Markus Hirsimäki

TL;DR:这是您的无依赖性跨平台最大密度复制意大利面

我知道我正在寻找那个☝️。你从谷歌来到这里,想要一些不需要 pip install this-and-that 的东西?我相当确定这个解决方案将继续工作很长时间。

示例使用

>>> getch_but_it_actually_works() # just normal key like a
'a'

>>> getch_but_it_actually_works() # a but its shift or capslock
'A'

>>> getch_but_it_actually_works() # just bare enter
'\r'

>>> getch_but_it_actually_works() # literal ESC key
'\x1b'

>>> getch_but_it_actually_works() # one of the arrow keys on linux
'\x1b[A'

>>> getch_but_it_actually_works() # one of the arrow keys on windows
'àK'

>>> getch_but_it_actually_works() # some really obscure key-combo. still works.
'\x1b[19;6~'

跨平台解决方案,无外部依赖

滚动以在末尾带有理智的缩进和评论以获取更详细的答案。这是便于复制粘贴的最大密度预览。只需调用 getch_but_it_actually_works()

import os
def _read_one_wide_char_win(): return msvcrt.getwch()
def _char_can_be_escape_win(char): return True if char in ("\x00", "à") else False
def _dump_keyboard_buff_win():
    try: msvcrt.ungetwch("a")
    except OSError: return msvcrt.getwch()
    else: _ = msvcrt.getwch(); return ""
def _read_one_wide_char_nix():
    old_settings = termios.tcgetattr(sys.stdin.fileno()); tty.setraw(sys.stdin.fileno())
    wchar = sys.stdin.read(1)
    termios.tcsetattr(sys.stdin.fileno(), termios.TCSANOW, old_settings); return wchar
def _char_can_be_escape_nix(char): return True if char == "\x1b" else False
def _dump_keyboard_buff_nix():
    old_settings = termios.tcgetattr(sys.stdin.fileno())
    tty.setraw(sys.stdin.fileno()); os.set_blocking(sys.stdin.fileno(), False)
    buffer_dump = ""
    while char := sys.stdin.read(1): buffer_dump += char
    os.set_blocking(sys.stdin.fileno(), True); termios.tcsetattr(sys.stdin.fileno(), termios.TCSANOW, old_settings)
    if buffer_dump: return buffer_dump
    else: return ""
if os.name == "nt":
    import msvcrt
    read_one_wdchar, char_can_escape, dump_key_buffer = _read_one_wide_char_win, _char_can_be_escape_win, _dump_keyboard_buff_win
if os.name == "posix":
    import termios, tty, sys
    read_one_wdchar, char_can_escape, dump_key_buffer = _read_one_wide_char_nix, _char_can_be_escape_nix, _dump_keyboard_buff_nix
def getch_but_it_actually_works():
    wchar = read_one_wdchar()
    if char_can_escape(wchar): dump = dump_key_buffer(); return wchar + dump
    else: return wchar

长答案,带有注释和合理缩进的代码

这是所有评论的长答案。仍然没有依赖关系。

这很可能会在 linux 和 windows 上工作很长时间。没有外部依赖,只有内置。

它还将处理边缘情况,例如按箭头键或诸如 之类的晦涩难懂的东西,这将在 linux 上产生长的 ANSI 转义序列,在 Windows 上产生其他东西。它将捕获诸如 或 tab 或 F1-12 之类的东西作为单个输入

这些年来,我已经多次回到这篇文章,所以现在是我退还两美分和利息的时候了。下面是完整注释的代码。

该示例有点长,但您可以跳过大部分内容。相关位在最后,您可以复制粘贴整个内容。


import os

def _read_one_wide_char_win():
    """Wait keyhit return chr. Get only 1st chr if multipart key like arrow"""
    return msvcrt.getwch()

def _char_can_be_escape_win(char):
    """Return true if char could start a multipart key code (e.g.: arrows)"""
    return True if char in ("\x00", "à") else False # \x00 is null character

def _dump_keyboard_buff_win():
    """If piece of multipart keycode in buffer, return it. Else return None"""
    try:                       # msvcrt.kbhit wont work with msvcrt.getwch
        msvcrt.ungetwch("a")   # check buffer status by ungetching wchr
    except OSError:            # ungetch fails > something in buffer so >
        return msvcrt.getwch() # return the buffer note: win multipart keys
    else:                      # are always 2 parts. if ungetwch does not fail
        _ = msvcrt.getwch()    # clean up and return empty string
        return ""

def _read_one_wide_char_nix():
    """Wait keyhit return chr. Get only 1st chr if multipart key like arrow"""
    old_settings = termios.tcgetattr(sys.stdin.fileno()) # save settings
    tty.setraw(sys.stdin.fileno()) # set raw mode to catch raw key w/o enter
    wchar = sys.stdin.read(1)
    termios.tcsetattr(sys.stdin.fileno(), termios.TCSANOW, old_settings)
    return wchar

def _char_can_be_escape_nix(char):
    """Return true if char could start a multipart key code (e.g.: arrows)"""
    return True if char == "\x1b" else False # "\x1b" is literal esc-key

def _dump_keyboard_buff_nix():
    """If parts of multipart keycode in buffer, return them. Otherwise None"""
    old_settings = termios.tcgetattr(sys.stdin.fileno()) # save settings
    tty.setraw(sys.stdin.fileno()) # raw to read single key w/o enter
    os.set_blocking(sys.stdin.fileno(), False) # dont block for empty buffer
    buffer_dump = ""
    while char := sys.stdin.read(1):
        buffer_dump += char
    os.set_blocking(sys.stdin.fileno(), True) # restore normal settings
    termios.tcsetattr(sys.stdin.fileno(), termios.TCSANOW, old_settings)
    if buffer_dump:
        return buffer_dump
    else:
        return ""

if os.name == "nt":
    import msvcrt
    read_one_wdchar = _read_one_wide_char_win
    char_can_escape = _char_can_be_escape_win
    dump_key_buffer = _dump_keyboard_buff_win
if os.name == "posix":
    import termios
    import tty
    import sys
    read_one_wdchar = _read_one_wide_char_nix
    char_can_escape = _char_can_be_escape_nix
    dump_key_buffer = _dump_keyboard_buff_nix


def getch_but_it_actually_works():
    """Returns a printable character or a keycode corresponding to special key
    like arrow or insert. Compatible with windows and linux, no external libs
    except for builtins. Uses different builtins for windows and linux.

    This function is more accurately called:
    "get_wide_character_or_keycode_if_the_key_was_nonprintable()"

    e.g.:
        * returns "e" if e was pressed
        * returns "E" if shift or capslock was on
        * returns "x1b[19;6~'" for ctrl + shift + F8 on unix

    You can use string.isprintable() if you need to sometimes print the output
    and sometimes use it for menu control and such. Printing raw ansi escape
    codes can cause your terminal to do things like move cursor three rows up.

    Enter will return "\ r" on all platforms (without the space seen here)
    as the enter key will produce carriage return, but windows and linux
    interpret it differently in different contexts on higher level
    """
    wchar = read_one_wdchar()    # get first char from key press or key combo
    if char_can_escape(wchar):   # if char is escapecode, more may be waiting
        dump = dump_key_buffer() # dump buffer to check if more were waiting.
        return wchar + dump      # return escape+buffer. buff could be just ""
    else:                        # if buffer was empty then we return a single
        return wchar             # key like "e" or "\x1b" for the ESC button

x
xro

我对 python3 的解决方案,不依赖于任何 pip 包。

# precondition: import tty, sys
def query_yes_no(question, default=True):
    """
    Ask the user a yes/no question.
    Returns immediately upon reading one-char answer.
    Accepts multiple language characters for yes/no.
    """
    if not sys.stdin.isatty():
        return default
    if default:
        prompt = "[Y/n]?"
        other_answers = "n"
    else:
        prompt = "[y/N]?"
        other_answers = "yjosiá"

    print(question,prompt,flush= True,end=" ")
    oldttysettings = tty.tcgetattr(sys.stdin.fileno())
    try:
        tty.setraw(sys.stdin.fileno())
        return not sys.stdin.read(1).lower() in other_answers
    except:
        return default
    finally:
        tty.tcsetattr(sys.stdin.fileno(), tty.TCSADRAIN , oldttysettings)
        sys.stdout.write("\r\n")
        tty.tcdrain(sys.stdin.fileno())

B
Ben Ogorek

接受的答案对我来说表现不佳(我会按住一个键,什么都不会发生,然后我会按另一个键,它会起作用)。

在了解了 curses 模块之后,这似乎是正确的方法。现在可以通过 windows-cursors(通过 pip 获得)在 Windows 上使用它,因此您可以以与平台无关的方式进行编程。以下是 YouTube 上受此 nice tutorial 启发的示例:

import curses                                                                                                                                       
def getkey(stdscr):
    curses.curs_set(0)
    while True:
        key = stdscr.getch()
        if key != -1:
            break
    return key

if __name__ == "__main__":
    print(curses.wrapper(getkey))

使用 .py 扩展程序保存它,或在交互模式下运行 curses.wrapper(getkey)


M
Meir Gabay

在这里回答:raw_input in python without pressing enter

使用此代码-

from tkinter import Tk, Frame


def __set_key(e, root):
    """
    e - event with attribute 'char', the released key
    """
    global key_pressed
    if e.char:
        key_pressed = e.char
        root.destroy()


def get_key(msg="Press any key ...", time_to_sleep=3):
    """
    msg - set to empty string if you don't want to print anything
    time_to_sleep - default 3 seconds
    """
    global key_pressed
    if msg:
        print(msg)
    key_pressed = None
    root = Tk()
    root.overrideredirect(True)
    frame = Frame(root, width=0, height=0)
    frame.bind("<KeyRelease>", lambda f: __set_key(f, root))
    frame.pack()
    root.focus_set()
    frame.focus_set()
    frame.focus_force()  # doesn't work in a while loop without it
    root.after(time_to_sleep * 1000, func=root.destroy)
    root.mainloop()
    root = None  # just in case
    return key_pressed


def __main():
        c = None
        while not c:
                c = get_key("Choose your weapon ... ", 2)
        print(c)

if __name__ == "__main__":
    __main()

参考:https://github.com/unfor19/mg-tools/blob/master/mgtools/get_key_pressed.py


V
Vinay Verma

如果您只想注册一个按键,即使用户按下它不止一次或按住按键的时间更长。为避免获得多个按下的输入,请使用 while 循环并传递它。

import keyboard

while(True):
  if(keyboard.is_pressed('w')):
      s+=1
      while(keyboard.is_pressed('w')):
        pass
  if(keyboard.is_pressed('s')):
      s-=1
      while(keyboard.is_pressed('s')):
        pass
  print(s)

keyboard 模块应该来自哪个包?是什么让你写 if():?这不是 C :)
M
Mabooka

内置 raw_input 应该会有所帮助。

for i in range(3):
    print ("So much work to do!")
k = raw_input("Press any key to continue...")
print ("Ok, back to work.")

raw_input 正在等待输入键
K
Khan Saad

如果您只想按住屏幕以便在终端上看到结果,只需编写

input()

在代码的末尾,它将保持屏幕


这没有回答问题。用户正在询问如何读取单个字符。