賦值之前引用的變量：Python

Question

我正在嘗試從樹莓派3到Azure的數據

該腳本從Raspberry Pi3讀取數據，Raspberry Pi3通過藍牙連接到傳感器並獲取多個值。
不幸的是，我在運行時遇到錯誤

“分配前已引用局部變量'溫度'”

def iothub_client_sample_run():
    msgs=[]

    for address, name in list(devices.items()):
    try:
        client = iothub_client_init()

        if client.protocol == IoTHubTransportProvider.MQTT & (name == "Flower care"):
       msg_txt_formatted = MSG_TXT % (
          temperature,
            sunlight,
            moisture,
            fertility)

            message = IoTHubMessage(msg_txt_formatted)
                # optional: assign ids
       message.temperature_id = "%d" % temperature

       client.send_event_async(message, send_confirmation_callback, devices.items())
       print ( "IoTHubClient.send_event_async accepted message {} for transmission to IoT Hub.".format(devices.items()) )
       return msgs      
while 1:
msgs=iothub_client_sample_run()
for msg in msgs:
print msg['topic']
print msg['payload']
(result, mid)=mqttc.publish(msg['topic'],msg['payload'])
print ( "Send status: %s" % status )
        time.sleep(10)
mqttc.disconnect()

except IoTHubError as iothub_error:
        print ( "Unexpected error %s from IoTHub" % iothub_error )
       return
except KeyboardInterrupt:
        print ( "IoTHubClient sample stopped" )
    print_last_message_time(client)

Answer 1

錯誤消息很清楚。

請記住，Python一次只能讀取和執行一行代碼，因此，如果在使用它的函數后有一個聲明的變量，那么它將拋出錯誤。 仔細處理代碼，以在調用變量之前放入變量，並且此錯誤不會再有任何問題。