Find a value in an array of objects in Javascript

Question

I know similar questions have been asked before  but this one is a little different  I have an array of unnamed objects  which contain an array of named objects  and I need to get the object where  name  is  string 1   Here is an example array   var array           name  string 1   value  this   other   that           name  string 2   value  this   other   that         Update  I should have said this earlier  but once I find it  I want to replace it with an edited object

User · Answer

New answer

I added the prop as a parameter, to make it more general and reusable

/**
 * Represents a search trough an array.
 * @function search
 * @param {Array} array - The array you wanna search trough
 * @param {string} key - The key to search for
 * @param {string} [prop] - The property name to find it in
 */

function search(array, key, prop){
    // Optional, but fallback to key['name'] if not selected
    prop = (typeof prop === 'undefined') ? 'name' : prop;    

    for (var i=0; i < array.length; i++) {
        if (array[i][prop] === key) {
            return array[i];
        }
    }
}

Usage:

var array = [
    { 
        name:'string 1', 
        value:'this', 
        other: 'that' 
    },
    { 
        name:'string 2', 
        value:'this', 
        other: 'that' 
    }
];

search(array, 'string 1');
// or for other cases where the prop isn't 'name'
// ex: prop name id
search(array, 'string 1', 'id');

Mocha test:

var assert = require('chai').assert;

describe('Search', function() {
    var testArray = [
        { 
            name: 'string 1', 
            value: 'this', 
            other: 'that' 
        },
        { 
            name: 'string 2', 
            value: 'new', 
            other: 'that' 
        }
    ];

    it('should return the object that match the search', function () {
        var name1 = search(testArray, 'string 1');
        var name2 = search(testArray, 'string 2');

        assert.equal(name1, testArray[0]);
        assert.equal(name2, testArray[1]);

        var value1 = search(testArray, 'this', 'value');
        var value2 = search(testArray, 'new', 'value');

        assert.equal(value1, testArray[0]);
        assert.equal(value2, testArray[1]);
    });

    it('should return undefined becuase non of the objects in the array have that value', function () {
        var findNonExistingObj = search(testArray, 'string 3');

        assert.equal(findNonExistingObj, undefined);
    });

    it('should return undefined becuase our array of objects dont have ids', function () {
        var findById = search(testArray, 'string 1', 'id');

        assert.equal(findById, undefined);
    });
});

test results:

Search
    ? should return the object that match the search
    ? should return undefined becuase non of the objects in the array have that value
    ? should return undefined becuase our array of objects dont have ids


  3 passing (12ms)

Old answer - removed due to bad practices

if you wanna know more why it's bad practice then see this article:

Why is extending native objects a bad practice?

~~Prototype version of doing an array search:~~

Array.prototype.search = function(key, prop){ for (var i=0; i < this.length; i++) { if (this[i][prop] === key) { return this[i]; } } }

Usage:

var array = [ { name:'string 1', value:'this', other: 'that' }, { name:'string 2', value:'this', other: 'that' } ]; array.search('string 1', 'name');

User · Answer

This answer is good for typescript   Angular 2  4  5    I got this answer with the help of  rujmah answer above   His answer brings in the array count    and then find s the value and replaces it with another value      What this answer does is simply grabs the array name that might be set in another variable via another module   component    in this case the array I build had a css name of stay-dates   So what this does is extract that name and then allows me to set it to another variable and use it like so   In my case it was an html css class     let obj   this highlightDays find x   gt  x css   let index   this highlightDays indexOf obj   console log  here we see what hightlightdays is    obj css   let dayCss   obj css

User · Answer

Another way  to aid  NullUserException and  Wexoni s comments  is to retrieve the object s index in the array and then go from there   var index   array map function obj   return obj name     indexOf  name-I-am-looking-for       Then we can access it to do whatever we want array index     name   newName   value   that   other   rocks

User · Answer

if you are using jQuery try   grep     http   api jquery com jquery grep

User · Answer

Considering you have following snippet   var array           name  string 1   value  this   other   that           name  string 2   value  this   other   that         You can use the following function to search for items  const search   what   gt  array find element   gt  element name     what     And you can check whether the item was found or not   if  search  string 1          console log search value  search other     else       console log  No result found

User · Answer

var array           name  string 1   value  this   other   that           name  string 2   value  this   other   that        var foundValue   array filter obj  gt obj name    string 1     console log foundValue

User · Answer

With a foreach   let itemYouWant   null  array forEach  item    gt        if  item name      string 1             itemYouWant   item            console log itemYouWant

User · Answer

with underscore js use the findWhere method   var array           name  string 1   value  this   other   that           name  string 2   value  this   other   that         var result     findWhere array   name   string 1      console log result name     See this in JSFIDDLE

User · Answer

Either use a simple for-loop   var result   null  for  var i   0  i  lt  array length  i         if  array i  name      string 1          result   array i       break           Or if you can  that is  if your browser supports it  use Array filter  which is much more terse   var result   array filter function  obj      return obj name      string 1      0

User · Answer

One line answer  You can use filter function to get result    x000D   x000D  var array     x000D        name  string 1   value  this   other   that     x000D        name  string 2   value  this   other   that    x000D     x000D   x000D  console log array filter function arr  return arr name     string 1    0    x000D   x000D   x000D

User · Answer

In ES6 you can use Array prototype find predicate  thisArg   like so   array find x   gt  x name      string 1     http   exploringjs com es6 ch arrays html  searching-for-array-elements https   developer mozilla org en docs Web JavaScript Reference Global Objects Array find  To then replace said object  and use another cool ES6 method fill  you could do something like   let obj   array find x   gt  x name      string 1    let index   array indexOf obj   array fill obj name  some new string   index  index

User · Answer

You can loop over the array and test for that property   function search nameKey  myArray       for  var i 0  i  lt  myArray length  i              if  myArray i  name     nameKey                return myArray i                      var array           name  string 1   value  this   other   that           name  string 2   value  this   other   that        var resultObject   search  string 1   array

User · Answer

function getValue        for var i   0   i lt  array length  i             var obj   array i           var arr   array  types            for var j   0  j lt arr length j                  if arr j      value                    return obj

User · Answer

Similar to previous answers I used the following       Array prototype getIemtByParam   function paramPair          var key   Object keys paramPair  0         return this find function item  return   item key     paramPair key     true  false             usage    myArray getIemtByParam       name   Sasha

User · Answer

Are you looking for generic Search Filter  across the item in the object list  without specifying the item key    Input  var productList     category   Sporting Goods   price    49 99   stocked  true  name   Football     category   Sporting Goods   price    9 99   stocked  true  name   Baseball     category   Sporting Goods   price    29 99   stocked  false  name   Basketball     category   Electronics   price    99 99   stocked  true  name   iPod Touch     category   Electronics   price    399 99   stocked  false  name   iPhone 5     category   Electronics   price    199 99   stocked  true  name   Nexus 7    function customFilter objList  text   if undefined     text    text          return objList  return objList filter product   gt        let flag      for let prop in product           flag   false          flag   product prop  toString   indexOf text   gt  -1          if flag          break        return flag         Execute  customFilter productList    9

User · Answer

You can do it with a simple loop   var obj   null      for  var i   0  i  lt  array length  i          if  array i  name     string 1             obj   array i           break

User · Answer

Finding the array element    x000D   x000D  let arr     x000D        name  string 1   value  this   other   that     x000D        name  string 2   value  this   other   that    x000D     x000D   x000D  let obj   arr find o   gt  o name      string 1    x000D   x000D  console log obj   x000D   x000D   x000D      Replacing the array element    x000D   x000D  let arr     x000D        name  string 1   value  this   other   that     x000D        name  string 2   value  this   other   that    x000D     x000D   x000D  let obj   arr find  o  i    gt    x000D      if  o name      string 1     x000D          arr i      name   new string   value   this   other   that     x000D          return true     stop searching x000D        x000D      x000D   x000D  console log arr   x000D   x000D   x000D

User · Answer

Here is the solution for search and replace  function searchAndUpdate name replace       var obj   array filter function   obj             return obj name     name         0       obj name   replace     searchAndUpdate  string 2   New String 2

User · Answer

As per ECMAScript 6  you can use  the findIndex function   array array findIndex x   gt  x name     string 1

User · Answer

You can use query-objects from npm  You can search an array of objects using filters   const queryable   require  query-objects     const users                 firstName   George         lastName   Eracleous         age  28                    firstName   Erica         lastName   Archer         age  50                    firstName   Leo         lastName   Andrews         age  20           const filters                 field   age         value  30        operator   lt                     field   firstName         value   Erica         operator   equals               Filter all users that are less than 30 years old AND their first name is Erica const res   queryable users  and filters       Filter all users that are less than 30 years old OR their first name is Erica const res   queryable users  or filters

[javascript] Find a value in an array of objects in Javascript

New answer

Old answer - removed due to bad practices

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