我不知道我做错了什么

Question

我试图调用类AQIparameters来向用户显示存储在函数aqi_parameters中的变量，但它只是在am参数中显示字符串。

我尝试在函数中调用aqiparameters类，但是它会导致位置错误或其他形式的错误。

类和函数所在的form.py

from AQI_WebApp_Flask import main_functions
import requests
from flask_wtf import FlaskForm
from wtforms import SelectField
import folium

class AQIParameters(FlaskForm):
    aqiparameter = SelectField('aqiparameter', choices=[("coordinates","coordinates"),
                                                      ("pr","pr"),
                                                      ("hu", "hu"),
                                                      ("aqius", "aqius")])


def aqi_parameter():
    url = "https://api.airvisual.com/v2/nearest_city?key="
    aqi_key = main_functions.read_from_file("AQI_WebApp_Flask/JSON_Files/aqi_key.json")
    aqi_key = aqi_key['aqi_key']

    url2 = url+aqi_key

    request_json = requests.get(url2).json()

    main_functions.save_to_file(request_json, "AQI_WebApp_Flask/JSON_Files/aqi.json")

    air_quality_index = main_functions.read_from_file("AQI_WebApp_Flask/JSON_Files/aqi.json")


    '''
    From the json file read above, please find the right values for the variables below
    Notice that I already accessed the values for latitude and longitude
    and I also concatenated them into one variable called coordinates
    '''

    latitude = air_quality_index['data']['location']['coordinates'][0]
    longitude = air_quality_index['data']['location']['coordinates'][1]
    coordinates = str(latitude)+', '+str(longitude)

    temperatureC = air_quality_index['data']['current']['weather']['tp']
    pressure = air_quality_index['data']['current']['weather']['pr']
    humidity = air_quality_index['data']['current']['weather']['hu']
    aqius = air_quality_index['data']['current']['pollution']['aqius']


    parameters = {'coordinates': coordinates,
                  'temperatureC': str(temperatureC),
                  'pressure': str(pressure),
                  'humidity': str(humidity),
                  'aqius': str(aqius)}


    return parameters

用户交互主要发生的routes.py

from AQI_WebApp_Flask import app, forms
from flask import request, render_template


@app.route('/', methods=['GET', 'POST'])
def search():
    searchForm = forms.AQIParameters(request.form)
    if request.method == "POST":

        parameters_requested = request.form['aqiparameter']
        aqi_parameter = forms.aqi_parameter()

        '''
        If the user makes a post request, please save the selected value by the user into a variable
        Also, call the function aqi_parameter (from forms.py) with all the results
        Then, render template parameter_result.html only with the parameter requested by the user
        Which means that you should assign the correct value for the variable parameter_requested below
        '''

        return render_template('parameter_result.html', result=parameters_requested, aqi_parameter=aqi_parameter)
    return render_template('parameter_search.html', form=searchForm)

Answer 1

看起来，您遇到的问题是，当您尝试访问模板中的aqi_parameter字典的值时，您使用的是字典键的字符串名称，而不是键本身。

例如，在模板中，您试图使用aqi_parameter.coordinates访问坐标值，但这将无法工作，因为坐标不是aqi_parameter对象的属性。相反，您需要使用方括号符号来访问字典的值，如下所示:aqi_parameter‘坐标’。

下面是一个如何在模板中访问aqi_parameter字典值的示例：

<p>Coordinates: {{ aqi_parameter['coordinates'] }}</p>
<p>Temperature: {{ aqi_parameter['temperatureC'] }}</p>
<p>Pressure: {{ aqi_parameter['pressure'] }}</p>
<p>Humidity: {{ aqi_parameter['humidity'] }}</p>
<p>AQI: {{ aqi_parameter['aqius'] }}</p>