indexOf method in an object array?

Question

What\'s the best method to get the index of an array which contains objects?

Imagine this scenario:

var hello = {
    hello: \'world\',
    foo: \'ba         


        

Answer 1

In ES2015, this is pretty easy:

myArray.map(x => x.hello).indexOf('stevie')

or, probably with better performance for larger arrays:

myArray.findIndex(x => x.hello === 'stevie')

Answer 2

Or prototype it :

Array.prototype.indexOfObject = function arrayObjectIndexOf(property, value) {
    for (var i = 0, len = this.length; i < len; i++) {
        if (this[i][property] === value) return i;
    }
    return -1;
}

myArr.indexOfObject("name", "stevie");

Answer 3

Try this:

console.log(Object.keys({foo:"_0_", bar:"_1_"}).indexOf("bar"));

https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/keys

Answer 4

simple:

myArray.indexOf(myArray.filter(function(item) {
    return item.hello == "stevie"
})[0])

Answer 5

You can simply use

const someId = 2;
const array = [{id:1}, {id:2}, {id:3}];
const index = array.reduce((i, item, index) => item.id === someId ? index : i, -1);
alert('someId ' + someId + ' is at index ' + index);

No underscore, no for, just a reduce.

Answer 6

Brief

myArray.indexOf('stevie','hello')

Use Cases :

  /*****NORMAL****/  
[2,4,5].indexOf(4) ;//OUTPUT 1
 /****COMPLEX*****/
 [{slm:2},{slm:4},{slm:5}].indexOf(4,'slm');//OUTPUT 1
 //OR
 [{slm:2},{slm:4},{slm:5}].indexOf(4,function(e,i){
   return e.slm;
});//OUTPUT 1
/***MORE Complex**/
[{slm:{salat:2}},{slm:{salat:4}},{slm:{salat:5}}].indexOf(4,function(e,i){
   return e.slm.salat;
});//OUTPUT 1

API :

    Array.prototype.indexOfOld=Array.prototype.indexOf

    Array.prototype.indexOf=function(e,fn){
      if(!fn){return this.indexOfOld(e)}
      else{ 
       if(typeof fn ==='string'){var att=fn;fn=function(e){return e[att];}}
        return this.map(fn).indexOfOld(e);
      }
    };