语音助手程序未收到指令触发UnboundLocalError问题求助

你的语音助手程序在提示“listening...”后3秒内未输入语音命令时，会触发UnboundLocalError导致崩溃。核心原因是take_command函数中command变量仅在try块内定义，当异常发生时（比如无语音输入），变量未被赋值就执行return，从而引发错误。

修复要点 #

• 提前初始化变量：在take_command函数开头定义command为None，确保无论是否触发异常，变量都有初始值
• 精准捕获异常：避免使用裸except，明确捕获语音识别相关的异常，方便排查问题
• 空值判断：在run_alexa中先检查command是否有效，无效则直接跳过后续逻辑，避免空值引发其他错误

修改后的完整代码 #

import speech_recognition as sr
import pyttsx3
import pywhatkit
import datetime
import wikipedia
import pyjokes

listener = sr.Recognizer()
engine = pyttsx3.init()
voices = engine.getProperty("voices")
engine.setProperty("voice", voices[0].id)


def talk(text):
    engine.say(text)
    engine.runAndWait()


def take_command():
    command = None  # 提前初始化变量，避免未赋值就返回
    try:
        with sr.Microphone() as source:
            print("listening...")
            # 设置超时时间（10秒无声音触发超时）和语音输入时长限制（最长5秒），可按需调整
            voice = listener.listen(source, timeout=10, phrase_time_limit=5)
            command = listener.recognize_google(voice)
            if "computer" in command:
                command = command.replace("computer", "").strip()
                print(command)
    except sr.WaitTimeoutError:
        # 超时无语音输入时的提示
        print("No voice input detected, waiting again...")
    except sr.UnknownValueError:
        # 无法识别语音时的反馈
        talk("Sorry, I didn't catch that.")
    except Exception as e:
        # 其他异常的兜底处理
        print(f"Error occurred: {e}")
    return command


def run_alexa():
    command = take_command()
    if not command:  # 无有效命令时直接返回，跳过后续逻辑
        return

    if "play" in command:
        song = command.replace("play", "").strip()
        talk(f"playing {song}")
        pywhatkit.playonyt(song)

    elif "time" in command:
        time = datetime.datetime.now().strftime("%I:%M %p")
        talk(f"the current time is {time}")

    elif "tell me about" in command:
        person = command.replace("tell me about", "").strip()
        try:
            info = wikipedia.summary(person, 1)
            talk(info)
        except wikipedia.exceptions.DisambiguationError:
            talk("There are multiple entries for that, please be more specific.")
        except wikipedia.exceptions.PageError:
            talk("I couldn't find information about that.")

    elif "your favourite artist" in command:
        talk("Mr worldwide aka pitbull")

    elif "joke" in command:
        talk(pyjokes.get_joke())

    else:
        talk("what are you talking about willis")


while True:
    run_alexa()

关键修改说明 #

1. 给take_command函数添加command = None初始化，彻底解决未赋值变量返回的问题
2. 为listener.listen设置超时参数，避免无限等待，同时明确异常类型处理
3. 在字符串替换后添加strip()，去除多余空格，提升命令识别准确性
4. 给维基百科查询添加异常处理，避免查询不到内容时程序崩溃
5. 在run_alexa开头增加空值判断，无效命令直接跳过后续逻辑，减少不必要的执行

内容的提问来源于stack exchange，提问作者Alexander