How do I search for a particular object within an array?

If you have an object reference, you can use indexOf itself, which does search for equality (two references are only equal if they point to the same object):

// Não se esqueça de usar var!
var arr = [];
var obj1 = {id: 1, nome: 'Wallace'}
arr.push(obj1);
arr.indexOf(obj1);

Otherwise, you need to check everything in the array until you find its object:

var arr = [];
arr.push({id: 1, nome: 'Wallace'});
for(var i=0; i<arr.length; i++) {
    if(arr[i].id === 1) {
        // achou!
    }
}

or (IE9 +):

var arr = [];
arr.push({id: 1, nome: 'Wallace'});
arr.forEach(function(el, i){
    if(el.id === 1) {
        // achou!
    }
});

or (IE9 +):

var arr = [];
arr.push({id: 1, nome: 'Wallace'});
var existe = arr.some(function(el, i){
    return el.id === 1;
});

These are just some of the possible methods. In the other answers you will see that you can also do with filter , map , among other methods.     

Why did not arr.indexOf({id: 1}); work?

The problem is that when you do arr.indexOf({id: 1}); you are creating a new object and not creating a twin / equal of the other that is already inside the array.

Notice that in JavaScript this gives false:

var a = {id: 1};
var b = {id: 1};
a == b // false

You have to use something that iterates through this array. For example .filter() .

Instead of looking for object I suggest using an array, or two parameters. Something like this:

function verificar(arr, procurar) {
    var chave = procurar[0];
    var valor = procurar[1];
    return !!arr.filter(function (el) {
        return el[chave] == valor;
    }).length;
}

jsFiddle: link

Hello,

You would do this as follows

function procurarIndice(arraySearch, atributo, valor){
   var cont=0;
   var indices=[];
   for(var i in arraySearch){
      var row = arraySearch[i];
      if(row[atributo]==valor){
         indices.push(cont)
      }
      cont++;
   }
   return indices;
}
arr = [];
arr.push({id: 1, nome: 'Wallace'});

procurarIndice(arr,"id",1);

The function would return an array of indexes, and to validate if the expected value exists, you could use an if by

if(procurarIndice(arr,"id",1).length>0){
   ...
}

Another solution is to use the .map (source :) method link )

The map() method invokes the callback function passed by argument for each element of Array and returns a new Array as a result.

var log = document.getElementById("menssagemLog");

arr = [];

arr.push({id: 1, nome: 'Wallace'});
arr.push({id: 2, nome: 'Carlos'});
arr.push({id: 3, nome: 'Livia'});

pos = arr.map(function(e) { return e.id; });
log.innerHTML += pos.indexOf(0)// Retorna -1
log.innerHTML += "<br/>"+pos.indexOf(1); // Retorna 0
log.innerHTML += "<br/>"+pos.indexOf(2); // Retorna 1
log.innerHTML += "<br/>"+pos.indexOf(4); // Retorna -1

console.log(log.innerHTML)

<div id="menssagemLog"></div>

var arr = [{id:1, desc:"1111"},{id:2, desc:"222"},{id:3, desc:"3333"},{id:4, desc:"4444"}];

arr.filter(function( obj ) {
  return obj.id == 1;
});