def on_message(client, userdata, msg): msg = json.loads(msg.payload) print(msg) daction = msg['items']['action']['value'] if daction[2] == '36': SSR.start_action_thread() SSR.runAction(action) SSR.change_action_value('11', 1) else: SSR.runAction(daction)怎么取action值

在这段代码中，`msg`是一个JSON格式的消息，需要使用`json.loads()`方法将其转换为Python字典对象。然后，可以使用`msg['items']['action']['value']`来获取`action`值。

所以，要取出`action`的值可以使用如下代码：

msg = json.loads(msg.payload)
action = msg['items']['action']['value']

这将把`action`的值存储在`action`变量中，可以在后续的代码中使用。在这段代码中，`daction`变量和`action`变量是相同的，因为它们都存储了相同的值。所以，可以将这段代码修改为：

msg = json.loads(msg.payload)
action = msg['items']['action']['value']
if action[2] == '36':
    SSR.start_action_thread()
    SSR.runAction(action)
    SSR.change_action_value('11', 1)
else:
    SSR.runAction(action)

这将根据`action`值的第三个字符是否为'36'来执行不同的操作。

相关问题

def on_message(client, userdata, msg): msg=json.loads(msg.payload) print(msg) action=msg['items']['action']['value'] if action == '0': SSR.start_action_thread() SSR.runAction(action) SSR.change_action_value('11',1) else: SSR.runAction(action)语法错误

这段代码中的语法错误是缩进错误。请参考下面的代码修复此问题：

def on_message(client, userdata, msg):
    msg = json.loads(msg.payload)
    print(msg)
    action = msg['items']['action']['value']
    if action == '0':
        SSR.start_action_thread()
        SSR.runAction(action)
        SSR.change_action_value('11', 1)
    else:
        SSR.runAction(action)

这是一个 MQTT 消息回调函数，当接收到消息时会被调用。函数中首先将消息的载荷解析为 JSON 格式，并打印出来。然后从消息中提取出 `action` 的值，根据这个值来执行不同的动作。如果 `action` 的值是字符串 `'0'`，则启动一个新线程执行动作，运行动作，修改动作的值为 `'11'`，否则只是运行动作。

modify the program so that this “b” no longer appears:import paho.mqtt.client as mqtt def on_connect(client,userdata,flags,rc): print("Connected with result code"+str(rc)) client.subscribe("hello/#") def on_message(client,userdata,msg): print(msg.topic+" "+str(msg.payload)) client=mqtt.Client() client.on_connect=on_connect client.on_message=on_message print("Connecting") client.connect("localhost",1883,60) client.loop_forever()

The "b" in the output can be removed by decoding the byte payload into a string. Here's the modified code:

import paho.mqtt.client as mqtt

def on_connect(client, userdata, flags, rc):
    print("Connected with result code " + str(rc))
    client.subscribe("hello/#")

def on_message(client, userdata, msg):
    print(msg.topic + " " + msg.payload.decode('utf-8'))  # Decode the byte payload to string

client = mqtt.Client()
client.on_connect = on_connect
client.on_message = on_message
print("Connecting")
client.connect("localhost", 1883, 60)
client.loop_forever()

By using the `decode('utf-8')` method on the `msg.payload`, we convert the byte payload to a string using the UTF-8 encoding. This ensures that the output no longer includes the "b" indicating a byte literal.