Javascript: How do I access an individual object in an object array, given one of the key's value's, without using a for loop? Is that possible?

Question

An object with an array of objects, and a function that returns all the names of each object in the array. This works.

 var persArr = {friends:[
     {name: "Adam", age: 37},
     {name: "Ben", age: 36},
     {name: "Chris", age: 46}],

     getFriend:function(){
         return this.friends.map(function(friend){
           return friend.name;
          }).join(', ').slice();
     }};

   var names = persArr.getFriend();

   console.log(names);

How can I return a name and age property of an object, based on search criteria?

   example: {name:"Chris", age:46}, 
            {name:"Ben",age: "36"} 

      perArr.getFriend("Chris");

you would have to make a new method name (eg. getFriendByName), and just loop through the array. — ergonaut, Oct 09 '15 at 00:53
You would need to loop over the Array to get the correct Object. — StackSlave, Oct 09 '15 at 00:55

Nishanth Matha · Accepted Answer · 2015-10-09T01:04:03.807

0

Just change your return function to return an object. Something like:

     getFriend:function(name){
         return this.friends.filter(function(friend){
          if(friend.name===name){
           return {name:friend.name, age:friend.age};}
          });
     }};

   var nameAge = persArr.getFriend('Adam');

   console.log(nameAge);

edited Oct 09 '15 at 01:04

answered Oct 09 '15 at 00:55

Nishanth Matha

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Thanks! Your answer is interesting. I wouldn't have thought to return the object like that, thanks. – Ronnie Headen Oct 09 '15 at 01:20

score 0 · Answer 2 · answered Oct 09 '15 at 00:55

0

Could change your function to use filter() instead of map:

 getFriend:function(name){
    var match = this.friends.filter(function(friend){
       return friend.name === name;
    });
     return match.length ? match[0] : false;
 }};

answered Oct 09 '15 at 00:55

charlietfl

170,828
13
121
150

Thank you! This is exactly what i wanted, except the age. I knew how to do it iterating through the array. My mind was just fuzzy thinking how to do it functionally. Also im new at this, just learning. thanks again. – Ronnie Headen Oct 09 '15 at 01:16

score 0 · Answer 3 · answered Oct 09 '15 at 00:57

You can iterate over the list and check if the name matches your search parameter. If it matches return the actual object. In case it doesn't find anything return undefined.

getFriend: function(name) {
    for (var i = 0; i < friends.length; i++) {
        if (friends[i].name == name) {
            return friends[i];
        }
    }
    return undefined;
}

Javascript: How do I access an individual object in an object array, given one of the key's value's, without using a for loop? Is that possible?

3 Answers3