对象返回数组的关键字搜索

Question

Beginning coder here taking a js course. I'm almost done with a higher order function lesson, but am stuck. I have an object containing 250 countries with different info. Example:

const countries = [
    {
      name: 'Afghanistan',
      capital: 'Kabul',
      languages: ['Pashto', 'Uzbek', 'Turkmen'],
      population: 27657145,
      flag: 
'https://restcountries.eu/data/afg.svg',
      currency: 'Afghan afghani'
    },
    {
      name: 'Åland Islands',
      capital: 'Mariehamn',
      languages: ['Swedish'],
      population: 28875,
      flag: 
'https://restcountries.eu/data/ala.svg',
      currency: 'Euro'
    }, etc.

I'm asked to write a function that searches each country's name and returns an array of only the countries meeting the keyword criteria. I'm stumped and feel very lost. Here's what I have:

const keys = Object.keys(countries)
function categorizeCountries(keyword) {
    for (let i = 0; i < keys.length; i++) {
        let country = countries.name
        if (country.includes(keyword)) {
            console.log(countries.filter((country) 
=> country.includes(keyword)))
     } else {
        console.log('Country not found')
        }
    }
    return country
}
categorizeCountries('land')
scategorizeCountries('stan')

I'm sure the issue is in my conditional statement, but I don't know how else to go about this. Any help is greatly appreciated.

Answer 1

This is a short snippet demonstrating how to do it with .filter() and .includes() (@IvanaMurray made a good point regarding the application of .toLowerCase() for the strings to be compared, which I have left out here for simplicity):

 const countries = [ { name: 'Afghanistan', capital: 'Kabul', languages: ['Pashto', 'Uzbek', 'Turkmen'], population: 27657145, flag: 'https://restcountries.eu/data/afg.svg', currency: 'Afghan afghani' }, { name: 'Åland Islands', capital: 'Mariehamn', languages: ['Swedish'], population: 28875, flag: 'https://restcountries.eu/data/ala.svg', currency: 'Euro' }]; ["land","stan","an"].forEach(s=> console.log(countries.filter(c=> c.name.includes(s))) )

Answer 2

When using Object.keys you only get the keys of the array. In your case just "0" and "1" . What you want is the values. And then it's quite easy to sort using the filter prototype.

 const countries = [ { name: 'Afghanistan', capital: 'Kabul', languages: ['Pashto', 'Uzbek', 'Turkmen'], population: 27657145, flag: 'https://restcountries.eu/data/afg.svg', currency: 'Afghan afghani' }, { name: 'Åland Islands', capital: 'Mariehamn', languages: ['Swedish'], population: 28875, flag: 'https://restcountries.eu/data/ala.svg', currency: 'Euro' }]; const countriesArray = Object.values(countries); function categorizeCountries(keyword) { console.log(countriesArray.filter(country => country.name.toLowerCase().includes(keyword.toLowerCase()))) } categorizeCountries('af')

Answer 3

you are looping incorrectly through countries (you don't need Object.keys and you omitted usage of i also you have to accamulate your result in array)

function categorizeCountries(keyword) {
    const result = [];
    for (let i = 0; i < countries.length; i++) {
        let { name } = countries[i];
        if (name.includes(keyword)) {
            console.log(name);
            result.push(name);
     } else {
        console.log('Country not found')
     }
    }
    return result;
}