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Create a function to sort an array of objects by their values in Javascript

This is an array of objects:

const movies = [
  {
    title: "Terminator",
    genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" },
  },
  {
    title: "Die Hard",
    genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" },
  },
  {
    title: "Get Out",
    genre: { _id: "5b21ca3eeb7f6fbccd471820", name: "Thriller" },
  },
]

I would like to sort them by title and genre.name .

I want to create 2 new arrays, one is sorted by title and the other one is sorted by genre.name .

So far I tried this, but it was clearly wrong:

 const sortMovies = (item) => {
  movies.sort((a, b) =>
   a.item> b.item? 1 : b.item> a.item? -1 : 0
   );
 };

const sortTitle = sortMovies(title);
const sortGenre = sortMovies(genre.name);

Please help me find a solution to this. I really appreciate it!

It seems that you want to compare title then genre.name .

So you can combine those criteria in this way

a.title.localeCompare(b.title) || a.genre.name.localeCompare(b.genre.name)

 const movies = [ { title: "Terminator", genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" }, }, { title: "Die Hard", genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" }, }, { title: "Get Out", genre: { _id: "5b21ca3eeb7f6fbccd471820", name: "B" }, }, { title: "Get Out", genre: { _id: "5b21ca3eeb7f6fbccd471820", name: "A" }, }, ]; const sortMovies = (data) => { data.sort((a, b) => a.title.localeCompare(b.title)|| a.genre.name.localeCompare(b.genre.name)); } sortMovies(movies); console.log(movies);

As you can see, title = Get Out is also sorted by genre.name


Edited

I want to create 2 new arrays, one is sorted by title and the other one is sorted by genre.name.

In case you want to create a generic method

  const sortMovies = (data, getValueByProp) => {
  data.sort((a, b) => 
  {
    const v1 = getValueByProp(a);
    const v2 = getValueByProp(b);
    return v1.localeCompare(v2);
  });
}
sortMovies(movies, (item) => item.title);
sortMovies(movies, (item) => item.genre.name);

 const movies = [ { title: "Terminator", genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" }, }, { title: "Die Hard", genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" }, }, { title: "Get Out", genre: { _id: "5b21ca3eeb7f6fbccd471820", name: "B" }, }, { title: "Get Out", genre: { _id: "5b21ca3eeb7f6fbccd471820", name: "A" }, }, ]; const sortMovies = (data, getValueByProp) => { data.sort((a, b) => { const v1 = getValueByProp(a); const v2 = getValueByProp(b); return v1.localeCompare(v2); }); } sortMovies(movies, (item) => item.title); console.log(movies); sortMovies(movies, (item) => item.genre.name); console.log(movies);

just change it like this

const sortMovies = (item) => {
       return movies.sort((a, b) =>
          a[item]> b[item]? 1 : b[item]> a[item]? -1 : 0
        );
      };
    
const sortTitle = sortMovies("title");

For more nested: I don't recommend this because of performance issue. Just to show the possibility

function getPropByString(obj, propString) {
    if (!propString)
        return obj;

    var prop, props = propString.split('.');

    for (var i = 0, iLen = props.length - 1; i < iLen; i++) {
        prop = props[i];

        var candidate = obj[prop];
        if (candidate !== undefined) {
            obj = candidate;
        } else {
            break;
        }
    }
    return obj[props[i]];
}
const sortMovies = (item) => {
    return movies.sort((a, b) =>
      getPropByString(a,item) > getPropByString(b,item)? 1 : getPropByString(b,item) > getPropByString(a,item) ? -1 : 0
    );
  };

  const sortTitle = sortMovies("title");
  const sortGenre = sortMovies("genre.name");

the following code snippet may help you

 const movies = [ { title: "Terminator", genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" }, }, { title: "Die Hard", genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" }, }, { title: "Get Out", genre: { _id: "5b21ca3eeb7f6fbccd471820", name: "Thriller" }, }, ]; //sort by title var sortedByTitle = movies.sort( (a, b) => { if(a.title < b.title) { return -1; } if(a.title > b.title) { return 1; } return 0; } ); console.log(sortedByTitle); //sort by genre var sortedGenre = movies.sort( (a, b) => { if(a.genre.name < b.genre.name) { return -1; } if(a.genre.name > b.genre.name) { return 1; } return 0; } ); console.log(sortedGenre);

A sort higher order function only takes 1/-1 so passing 0 shouldn't work as far as I know.. But if you wanna sort the items as the item provided by the sortMovies function argument you have to do the following:

 const movies = [ { title: "Terminator", genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" }, }, { title: "Die Hard", genre: { _id: "5b21ca3eeb7f6fbccd471818", name: "Action" }, }, { title: "Get Out", genre: { _id: "5b21ca3eeb7f6fbccd471820", name: "Thriller" }, }, ] let sortsMovies = (properties) => { return movies.sort((a, b) => { try { const propertyArr = properties.split("."); // this gets properties from the end of the object nest const props1 = propertyArr.reduce((obj, prop) => obj[prop], a); const props2 = propertyArr.reduce((obj, prop) => obj[prop], b); return props1 > props2? 1: -1; } catch (error) { console.error('error:', error) } }); } const genre = sortsMovies("genre.name") const title = sortsMovies("title") console.log('title:', title) console.log('genre:', genre)

This should sort the Array of Object with the provided property

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