Nodejs Utililty Methods Array Search

Array.prototype.searchById = function(id){
  for(var i=0; i<this.length; i++){
    if(this[i].id === id){
      return this[i];
};

"use strict";
Array.prototype.searchIndex = function(n){
  var result = [],
      i,
      l= this.length;
  for( i= 0; i< l; i++){
    if(this[i] == n){
      result.push(i);
  if(result.length == 0){
    result.push(-1);
  return result;
};
 var arr = [1,2,5,5,5,5,5,6,9];
console.log(arr.searchIndex(5));
console.log(arr.searchIndex(0));

'use strict';
Array.prototype.searchObject = function (filterParams) {
    return this.filter(function (v) {
        return recursiveMatchFunc(v, filterParams);
    });
};
Array.prototype.randomSelect = function () {
    return this[Math.floor(Math.random() * this.length)];
};
...