Question

我创建了一个函数来将纬度和经度存储到全局变量中，以便可以将它们作为参数传递给另一个函数，但是我无法使其正常工作。我通过将一个函数放到另一个函数中解决了这个问题，但是对于为什么我原来的方法不起作用感到困惑？

下面的代码来自于getCordinates函数将值传递到getWeather函数中时，这些值不应该存储在全局变量中。

---这里是主应用的星级---

console.log("Server starting")

const yargs = require("yargs");
const geocode = require("./geocode/geocode");
const weather = require("./weather/weather");
const request = require('request');
let cordinates = {
    lat: 0,
    lng: 0
}

const argv = yargs.options({
    a:{
        demand: true,
        alias: 'address',
        describe: 'Address to fetch weather for',
        string: true
    }
}).help().alias('help', 'h').argv;

geocode.getCordinates(argv.a, (errorMessage, results) => {
    if(errorMessage){
        console.log(errorMessage);
        console.log(results)
    }else{
        console.log(`${results.address} - ${results.city} ${results.state}, ${results.country}`)



    }

});

    weather.getWeather(cordinates.lat, cordinates.lng, (errorMessage, weatherResults) => {
                if(errorMessage){
                    console.log(errorMessage);
                    console.log(results);

                }   else {
                        console.log(`The current temperature is ${weatherResults.temp} degrees celcius, and it feels like ${weatherResults.feelsLike}.`)

        }
    });

---主应用程序到此为止---

--- getCordinates函数从此处开始---

var getCordinates = (address, callback) =>{

    request({
    url: `http://www.mapquestapi.com/geocoding/v1/address?key=Dfgu2XcWvcvlYAbkz3B8gXr2z6SfTKtO&location=${encodeURIComponent(address)}`,
    json: true
}, (error, response, body) => {
    if(error){
        callback("Unable to connect to mapquest servers.", "Jack make big fart will be passed to the callback function as the results parameter.")      
    }else if(body.info.statuscode !== 0 && body.info.statuscode !== 200){
        callback("This location does not exist, please try again");
    } else{
        callback(undefined, {
            address: body.results[0].providedLocation.location.toUpperCase(),
            city:body.results[0].locations[0].adminArea5,
            state:body.results[0].locations[0].adminArea3,
            country:body.results[0].locations[0].adminArea1,
            lat:body.results[0].locations[0].latLng.lat,
            long:body.results[0].locations[0].latLng.lng
        });
    }   
});


}

--- getCordinates函数到此结束---

--- getWeather功能从此处开始---

let tempConverter = (farenheit) => {
    return Math.round((farenheit - 32) * 5 / 9)
};


let getWeather = (latitude, longitude, callback) =>{

request({
    url:`https://api.darksky.net/forecast/d32506e0e791e1ea3d7f55f24f43b2ba/${latitude},${longitude}`, 
    json:true
}, (error, response, body) => {
    if(error){
        callback("Unable to connect to forecast.io servers.", error)
    }else if(response.statusCode === 400){
        callback(body.error)

    }else if(response.statusCode === 403){
        callback(response.statusCode, response.statusMessage)
    }else {
        callback(undefined, {
            temp: tempConverter(body.currently.temperature),
            feelsLike: tempConverter(body.currently.apparentTemperature)

        });
    }
});


};

编辑：我添加了其他代码。抱歉，我之前没有添加！

全局变量未作为参数传递给我的函数

0 个答案: