将 json 数据转换为 python 中的变量的问题
Issues with turning json data into an variable in python
我一直在做一个教育项目，其中一小部分要求我将单行 json 数据转换为 python 3 中的一个变量，我从 domoticz（一个外部开源软件）但是由于我在 json 方面的技能水平，我遇到了一些问题，我不确定我做错了什么。我确实每次都收到 200 响应，所以根据我的理解，我假设这意味着连接不是问题，而是 python 代码。 （我删除了地址，但它们是正确的。）
The code im using:
import time
import re
import requests
from ctypes import c_int, c_char_p, byref, sizeof, c_uint16, c_int32, c_byte
from ctypes import c_void_p
from datetime import datetime
import os
import urllib.request
import json
import logging
import sys
from requests.exceptions import HTTPError
logger = logging.getLogger(__name__)
domoticzserver='ip'
switchid='3'
device='5'
tempbed=str(4)
def domoticzrequest (url):
request = urllib.request.Request(url)
response = urllib.request.urlopen(request)
return response.read()
import urllib.request, json
with urllib.request.urlopen("http://domoticzip/json.htm?type=devices&rid=4") as url:
data = json.loads(url.read().decode())
print(data)
json 我回来了，我可以通过单击 python 中的 url 来查看：
{
"ActTime" : 1606722346,
"AstrTwilightEnd" : "18:37",
"AstrTwilightStart" : "06:23",
"CivTwilightEnd" : "17:14",
"CivTwilightStart" : "07:47",
"DayLength" : "08:08",
"NautTwilightEnd" : "17:56",
"NautTwilightStart" : "07:04",
"ServerTime" : "2020-11-30 08:45:46",
"SunAtSouth" : "12:30",
"Sunrise" : "08:26",
"Sunset" : "16:34",
"app_version" : "2020.2",
"result" :
[
{
"AddjMulti" : 1.0,
"AddjMulti2" : 1.0,
"AddjValue" : 0.0,
"AddjValue2" : 0.0,
"BatteryLevel" : 255,
"CustomImage" : 0,
"Data" : "Normal",
"Description" : "",
"Favorite" : 0,
"HardwareID" : 1,
"HardwareName" : "Domoticz Internal",
"HardwareType" : "Domoticz Internal interface",
"HardwareTypeVal" : 67,
"HaveDimmer" : false,
"HaveGroupCmd" : false,
"HaveTimeout" : false,
"ID" : "148702",
"LastUpdate" : "2020-10-19 15:10:02",
"MaxDimLevel" : 0,
"Name" : "Domoticz Security Panel",
"Notifications" : "false",
"PlanID" : "0",
"PlanIDs" :
[
0
],
"Protected" : false,
"ShowNotifications" : true,
"SignalLevel" : "-",
"Status" : "Normal",
"StrParam1" : "",
"StrParam2" : "",
"SubType" : "Security Panel",
"SwitchType" : "Security",
"SwitchTypeVal" : 0,
"Timers" : "false",
"Type" : "Security",
"TypeImg" : "security",
"Unit" : 0,
"Used" : 0,
"XOffset" : "0",
"YOffset" : "0",
"idx" : "2"
},
{
"AddjMulti" : 1.0,
"AddjMulti2" : 1.0,
"AddjValue" : 0.0,
"AddjValue2" : 0.0,
"BatteryLevel" : 255,
"CustomImage" : 0,
"Data" : "-5.0 C",
"Description" : "",
"Favorite" : 1,
"HardwareID" : 2,
"HardwareName" : "Test sensor",
"HardwareType" : "Dummy (Does nothing, use for virtual switches only)",
"HardwareTypeVal" : 15,
"HaveTimeout" : true,
"ID" : "14053",
"LastUpdate" : "2020-11-09 09:03:34",
"Name" : "Temperatuur Kachel",
"Notifications" : "false",
"PlanID" : "0",
"PlanIDs" :
[
0
],
"Protected" : false,
"ShowNotifications" : true,
"SignalLevel" : "-",
"SubType" : "LaCrosse TX3",
"Temp" : -5.0,
"Timers" : "false",
"Type" : "Temp",
"TypeImg" : "temperature",
"Unit" : 1,
"Used" : 1,
"XOffset" : "0",
"YOffset" : "0",
"idx" : "3",
"trend" : 0
},
{
"AddjMulti" : 1.0,
"AddjMulti2" : 1.0,
"AddjValue" : 0.0,
"AddjValue2" : 0.0,
"BatteryLevel" : 255,
"CustomImage" : 0,
"Data" : "17.5",
"Description" : "",
"Favorite" : 1,
"HardwareID" : 3,
"HardwareName" : "Test switch",
"HardwareType" : "Dummy (Does nothing, use for virtual switches only)",
"HardwareTypeVal" : 15,
"HaveTimeout" : true,
"ID" : "0014054",
"LastUpdate" : "2020-11-06 11:51:09",
"Name" : "Temperatuur gewenst",
"Notifications" : "false",
"PlanID" : "0",
"PlanIDs" :
[
0
],
"Protected" : false,
"SetPoint" : "17.5",
"ShowNotifications" : true,
"SignalLevel" : "-",
"SubType" : "SetPoint",
"Timers" : "false",
"Type" : "Thermostat",
"TypeImg" : "override_mini",
"Unit" : 1,
"Used" : 1,
"XOffset" : "0",
"YOffset" : "0",
"idx" : "4"
}
],
"status" : "OK",
"title" : "Devices"
}
基本上我想要 SetPoint（在文本的最后一个选项卡中，也在这个正上方），在这个实例中是 17.5 作为 python 中的一个变量，我将使 python 代码循环，所以它每次都会抓取 json url 来更新设定值的状态。但是我只有抓住 17.5 才能将其变成变量时遇到问题。我最终得到了整个 json 就像这段代码所做的那样。或者如果我改变一些东西，我最终会得到过去的一切，包括设定点。有谁知道我做错了什么，可能我应该在哪里寻找解决方案？我对 python 的 json 部分有点陌生，我不知道从哪里开始，因为我发现并尝试过的代码似乎不起作用或给我错误。
非常感谢您的宝贵时间！
您正在将数据作为字典存储在 data ={"key": argument} 中。
如果你想访问某个值，你必须调用它。在你的情况下：
SetPoint = float(data["result"][-1]["SetPoint"])
分解：
data["result"] # gives you a list which elements are dictionaries.
the [-1] # calls for the last element in you list which contains the SetPoint
["SetPoint"] # then calls for the SetPoint Value which is a String "17.5"
float(...) converts the string to a float value
json.loads returns 一个 python 字典所以也许这样的事情会做：
result = json['result']
set_point = 0.0
for res in result:
if 'SetPoint' in res:
set_point = res['SetPoint']
我一直在做一个教育项目，其中一小部分要求我将单行 json 数据转换为 python 3 中的一个变量，我从 domoticz（一个外部开源软件）但是由于我在 json 方面的技能水平，我遇到了一些问题，我不确定我做错了什么。我确实每次都收到 200 响应，所以根据我的理解，我假设这意味着连接不是问题，而是 python 代码。 （我删除了地址，但它们是正确的。）
The code im using:
import time
import re
import requests
from ctypes import c_int, c_char_p, byref, sizeof, c_uint16, c_int32, c_byte
from ctypes import c_void_p
from datetime import datetime
import os
import urllib.request
import json
import logging
import sys
from requests.exceptions import HTTPError
logger = logging.getLogger(__name__)
domoticzserver='ip'
switchid='3'
device='5'
tempbed=str(4)
def domoticzrequest (url):
request = urllib.request.Request(url)
response = urllib.request.urlopen(request)
return response.read()
import urllib.request, json
with urllib.request.urlopen("http://domoticzip/json.htm?type=devices&rid=4") as url:
data = json.loads(url.read().decode())
print(data)
json 我回来了，我可以通过单击 python 中的 url 来查看：
{
"ActTime" : 1606722346,
"AstrTwilightEnd" : "18:37",
"AstrTwilightStart" : "06:23",
"CivTwilightEnd" : "17:14",
"CivTwilightStart" : "07:47",
"DayLength" : "08:08",
"NautTwilightEnd" : "17:56",
"NautTwilightStart" : "07:04",
"ServerTime" : "2020-11-30 08:45:46",
"SunAtSouth" : "12:30",
"Sunrise" : "08:26",
"Sunset" : "16:34",
"app_version" : "2020.2",
"result" :
[
{
"AddjMulti" : 1.0,
"AddjMulti2" : 1.0,
"AddjValue" : 0.0,
"AddjValue2" : 0.0,
"BatteryLevel" : 255,
"CustomImage" : 0,
"Data" : "Normal",
"Description" : "",
"Favorite" : 0,
"HardwareID" : 1,
"HardwareName" : "Domoticz Internal",
"HardwareType" : "Domoticz Internal interface",
"HardwareTypeVal" : 67,
"HaveDimmer" : false,
"HaveGroupCmd" : false,
"HaveTimeout" : false,
"ID" : "148702",
"LastUpdate" : "2020-10-19 15:10:02",
"MaxDimLevel" : 0,
"Name" : "Domoticz Security Panel",
"Notifications" : "false",
"PlanID" : "0",
"PlanIDs" :
[
0
],
"Protected" : false,
"ShowNotifications" : true,
"SignalLevel" : "-",
"Status" : "Normal",
"StrParam1" : "",
"StrParam2" : "",
"SubType" : "Security Panel",
"SwitchType" : "Security",
"SwitchTypeVal" : 0,
"Timers" : "false",
"Type" : "Security",
"TypeImg" : "security",
"Unit" : 0,
"Used" : 0,
"XOffset" : "0",
"YOffset" : "0",
"idx" : "2"
},
{
"AddjMulti" : 1.0,
"AddjMulti2" : 1.0,
"AddjValue" : 0.0,
"AddjValue2" : 0.0,
"BatteryLevel" : 255,
"CustomImage" : 0,
"Data" : "-5.0 C",
"Description" : "",
"Favorite" : 1,
"HardwareID" : 2,
"HardwareName" : "Test sensor",
"HardwareType" : "Dummy (Does nothing, use for virtual switches only)",
"HardwareTypeVal" : 15,
"HaveTimeout" : true,
"ID" : "14053",
"LastUpdate" : "2020-11-09 09:03:34",
"Name" : "Temperatuur Kachel",
"Notifications" : "false",
"PlanID" : "0",
"PlanIDs" :
[
0
],
"Protected" : false,
"ShowNotifications" : true,
"SignalLevel" : "-",
"SubType" : "LaCrosse TX3",
"Temp" : -5.0,
"Timers" : "false",
"Type" : "Temp",
"TypeImg" : "temperature",
"Unit" : 1,
"Used" : 1,
"XOffset" : "0",
"YOffset" : "0",
"idx" : "3",
"trend" : 0
},
{
"AddjMulti" : 1.0,
"AddjMulti2" : 1.0,
"AddjValue" : 0.0,
"AddjValue2" : 0.0,
"BatteryLevel" : 255,
"CustomImage" : 0,
"Data" : "17.5",
"Description" : "",
"Favorite" : 1,
"HardwareID" : 3,
"HardwareName" : "Test switch",
"HardwareType" : "Dummy (Does nothing, use for virtual switches only)",
"HardwareTypeVal" : 15,
"HaveTimeout" : true,
"ID" : "0014054",
"LastUpdate" : "2020-11-06 11:51:09",
"Name" : "Temperatuur gewenst",
"Notifications" : "false",
"PlanID" : "0",
"PlanIDs" :
[
0
],
"Protected" : false,
"SetPoint" : "17.5",
"ShowNotifications" : true,
"SignalLevel" : "-",
"SubType" : "SetPoint",
"Timers" : "false",
"Type" : "Thermostat",
"TypeImg" : "override_mini",
"Unit" : 1,
"Used" : 1,
"XOffset" : "0",
"YOffset" : "0",
"idx" : "4"
}
],
"status" : "OK",
"title" : "Devices"
}
基本上我想要 SetPoint（在文本的最后一个选项卡中，也在这个正上方），在这个实例中是 17.5 作为 python 中的一个变量，我将使 python 代码循环，所以它每次都会抓取 json url 来更新设定值的状态。但是我只有抓住 17.5 才能将其变成变量时遇到问题。我最终得到了整个 json 就像这段代码所做的那样。或者如果我改变一些东西，我最终会得到过去的一切，包括设定点。有谁知道我做错了什么，可能我应该在哪里寻找解决方案？我对 python 的 json 部分有点陌生，我不知道从哪里开始，因为我发现并尝试过的代码似乎不起作用或给我错误。 非常感谢您的宝贵时间！
您正在将数据作为字典存储在 data ={"key": argument} 中。
如果你想访问某个值，你必须调用它。在你的情况下：
SetPoint = float(data["result"][-1]["SetPoint"])
分解：
data["result"] # gives you a list which elements are dictionaries.
the [-1] # calls for the last element in you list which contains the SetPoint
["SetPoint"] # then calls for the SetPoint Value which is a String "17.5"
float(...) converts the string to a float value
json.loads returns 一个 python 字典所以也许这样的事情会做：
result = json['result']
set_point = 0.0
for res in result:
if 'SetPoint' in res:
set_point = res['SetPoint']