CODEWITHSUNDEEP
javascriptarrays
Gregori Roberts
Gregori Roberts

Reputation: 309

The method filter JS

There is a function that returns an array according to the second argument (if the country is Japan, it will return only brands of cars from Japan). Is it possible to improve the function using only the filter method?

const arr = [
   {  
     "name":"BMW",
     "price":"55 000",
     "country":"Germany",
     "sertificate":"yes"
  },
  {  
    "name":"Mercedes-benz",
    "price":"63 000", 
    "country":"Germany",
    "certificate":"yes"
  },
  {  
    "name":"Mitsubishi",
    "price":"93 000", 
    "constructor":"Bar John",
    "door":"3",
    "country":"Japan",
  },
  {  
    "name":"TOYOTA", 
    "price":"48 000", 
    "max_people":"7",
    "country":"Japan",
    "certificate":"yes"
  },
  {  
    "name":"Volkswagen",
    "price":"36 000", 
    "constructor":"Pier Sun",
    "country":"Germany",
    "certificate":"no"
  },
 ];

 function getCountry(arr, country) {
   let obj = arr.filter(function(arr){
      return arr.country === country ? arr.country : '';
   });
   let itemCountry = [{}];
   let newItem = 0;
   Object.keys(obj).forEach (item => (obj[item]!==null) ? (itemCountry[newItem]=obj[item] , newItem++): '');
   return itemCountry;
}

console.log(getCountry(arr,"Japan"));  // or any other country

Upvotes: 2

Views: 93

Answers (4)

Maheer Ali
Maheer Ali

Reputation: 36564

I think there is no need of any code after filter().Here is the version using Arrow Functions

const arr = [ { "name":"BMW", "price":"55 000", "country":"Germany", "sertificate":"yes" }, { "name":"Mercedes-benz", "price":"63 000", "country":"Germany", "sertificate":"yes" }, { "name":"Mitsubishi", "price":"93 000", "constructor":"Bar John", "door":"3", "country":"Japan", }, { "name":"TOYOTA", "price":"48 000", "max_people":"7", "country":"Japan", "sertificate":"yes" }, { "name":"Volkswagen", "price":"36 000", "constructor":"Pier Sun", "country":"Germany", "sertificate":"no" }, ];

const getCountry = (arr, country) => arr.filter(x => x.country === country);
console.log(getCountry(arr,"Japan"));

Upvotes: 2

Fullstack Guy
Fullstack Guy

Reputation: 16908

Yes you can only use Array.filter for this.

Using the destructuring assignment {country} in the arrow function, just pluck the country property from the array of objects and use it for comparison with the supplied country filter criteria:

const arr = [ { "name":"BMW", "price":"55 000", "country":"Germany", "sertificate":"yes" }, { "name":"Mercedes-benz", "price":"63 000", "country":"Germany", "sertificate":"yes" }, { "name":"Mitsubishi", "price":"93 000", "constructor":"Bar John", "door":"3", "country":"Japan", }, { "name":"TOYOTA", "price":"48 000", "max_people":"7", "country":"Japan", "sertificate":"yes" }, { "name":"Volkswagen", "price":"36 000", "constructor":"Pier Sun", "country":"Germany", "sertificate":"no" }, ];
function getCountry(arr, filterCountry) {
   return arr.filter(({country}) => {
      return country === filterCountry;
   });
}

console.log(getCountry(arr,"Japan"));  // or any other country

Upvotes: 0

Nina Scholz
Nina Scholz

Reputation: 386540

You could go a step ahead and use an abstract solution, where you can add a key and a wanted value for filtering the array.

const
    getItems = (array, key, value) => array.filter(o => o[key] === value),
    data = [{ name: "BMW", price: "55 000", country: "Germany", sertificate: "yes" }, { name: "Mercedes-benz", price: "63 000", country: "Germany", certificate: "yes" }, { name: "Mitsubishi", price: "93 000", constructor: "Bar John", door: "3", country: "Japan" }, { name: "TOYOTA", price: "48 000", max_people: "7", country: "Japan", certificate: "yes" }, { name: "Volkswagen", price: "36 000", constructor: "Pier Sun", country: "Germany", certificate: "no" }];

console.log(getItems(data, "country", "Japan"));
.as-console-wrapper { max-height: 100% !important; top: 0; }

Upvotes: 1

bjupreti
bjupreti

Reputation: 353

I think this should help.

arr.filter(i => i.country === "Japan");

You can learn more about filter here.

Upvotes: 1

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