python方法调用

Question

部分代码:

#打开串口
ser=serial.Serial('COM3', 9600)
#开启一个线程
th=threading.Thread(target=thread_read, args=(ser, msg_parsed))
th.start()

def thread_read(ser, callback=None):
     buf=b' '
     while running.is_set():
            buf=read_data(ser, buf,callback=None)

def read_data(ser, buf, callback=None):
     if callback is None:
            callback=print
     buf +=  ser.read(ser.inwaiting())

为啥在read_data()这个方法里调用inwaiting(),报错，告诉我has no attribute 'inwaiting()',在方法外面写ser.inwaiting()正常，我不是已经把serial对象的引用传入方法中了吗？书大神解答！

Answer 1

你别传对象，用全局变量试试

Answer 2

print(dir(ser))打印ser的所有方法,找到inWaiting和in_waiting，没有inwaiting，所以报错。
你确定在外面调用的是inwaiting吗？

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, '__eq__', '__exit__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__'
, '__iter__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__next__', '__reduce__', '__re
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', 'stopbits', 'tell', 'timeout', 'truncate', 'writable', 'write', 'writeTimeout', 'write_timeout',
'writelines', 'xonxoff']