我正在通过网络使用 UDP 数据包发送此温度和湿度读数,但是。由于 UDP 只接受 1 个参数,我将它们放入一个 JSON 对象然后是一个字符串。当我收到数据包时,我似乎无法从接收到的数据包中获取我想要的值
#!/usr/bin/python
import sys
import time
import socket
import Adafruit_DHT
import json
UDP_IP = "192.168.42.18"
PORT = 5001
my_ip = socket.gethostbyname(socket.getfqdn())
print "server has started",
while True:
humidity, temperature = Adafruit_DHT.read_retry(11, 4)#initialising DHT11 temp sensor
print 'Temp: {0:0.1f} C Humidity: {1:0.1f} %'.format(temperature, humidity)
print time.asctime()#printing to the terminal values
json_string = {}
json_string ['details'] = {'ip': my_ip, 'temp':temperature, 'humidity':humidity}
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)#initalising socket and UDP connection
Message = str(json_string)
print 'Message sent:= ', Message
sock.sendto(Message,(UDP_IP, PORT))
print "SENT to:-", UDP_IP, PORT, "From", my_ip
time.sleep(3)#delay
接收码
import socket
import time
import json
port = 5001
sock = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
sock.bind(("", port))
print "server started"
while True:
recieved = sock.recvfrom(1024)
print type(recieved)
print recieved[0]
print time.asctime()#bytes object
json_obj = json.dumps(recieved)
print type(json_obj)
print json_obj ['details']['temp']
#json_converted = json.loads(json_obj)
#print type(json_converted)
#json_string = map(str,(json_converted))
print "converted Json:- "
#print json_string['details']['temp']
print "Temperature in Celsuius"
我不断收到错误格式的错误。正确的方法是什么。
server started
<type 'tuple'>
{'details': {'ip': '127.0.1.1', 'temp': 20.0, 'humidity': 49.0}}
Wed Feb 22 16:27:06 2017
<type 'str'>
Traceback (most recent call last):
File "/Users/Faiz/Desktop/Rpi_Sensors_UDP/sensor_listenerUDP.py", line 24, in <module>
print json_obj ['details']['temp']
TypeError: string indices must be integers, not str
Process finished with exit code 1
最佳答案
在
使用 json.loadsjson_obj = json.loads(recieved[0])
代替
json_obj = json.dumps(recieved)
json.loads 会将你收到的字符串转换成dict,然后你就可以得到你的数据
像这样
import socket
import time
import json
port = 5001
sock = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
sock.bind(("", port))
print "server started"
while True:
recieved = sock.recvfrom(1024)
print type(recieved)
print recieved[0]
print time.asctime()#bytes object
json_obj = json.loads(recieved[0])
print type(json_obj)
print json_obj.get('details').get('temp')
#json_converted = json.loads(json_obj)
#print type(json_converted)
#json_string = map(str,(json_converted))
print "converted Json:- "
#print json_string['details']['temp']
print "Temperature in Celsuius"
关于Python:如何从 UDP 接收数据包中获取 JSON 对象,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/42397511/