python方法調用

Question

部分程式碼:

#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())

為啥在read_data()這個方法裡調用inwaiting(),報錯，告訴我has no attribute 'inwaiting()',在方法外面寫ser.inwaiting()正常，我不是已經把serial物件的引用傳入方法中了嗎？書大神解答！

Answer 1

你別傳對象，用全域變數試試

Answer 2

print(dir(ser))印ser的所有方法,找到inWaiting和in_waiting，沒有inwaiting，所以報錯。
你確定在外面調用的是inwaiting嗎？

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