javascript - Getting error [object HTMLCollection] -

i having problem in making simple test in javascript. quick example. each question's div id incremented in html code.

html

<form action="#">     <div id="q1">         <label>q. abcd</label>         <label><input type="radio" name="radio1" value="1">a</label>         <label><input type="radio" name="radio1" value="2">b</label>         <label><input type="radio" name="radio1" value="3">c</label>         <label><input type="radio" name="radio1" value="4">d</label>     </div>     ....     ....     <input type="button" value="click submit" onclick="result();"> </form> 

js (say 10 questions)

function result() {     var answer = new array();     for(var i=1; i<11 ; i++) {         if(document.getelementbyid("q" + i).getelementsbytagname("input") != undefined) {             answer[i] = document.getelementbyid("q" + i).getelementsbytagname("input");         }         else {             answer[i] = 0;         }     }     console.log(answer); } 

i getting error [object htmlcollection] every time submit code. how should can value of each answer given inside array , if doesn't answer question, array must 0 value @ place instead of undefined. need pure js , html solution.

try one

function result() {     var answer = new array();     // there no answer 0     answer[0] = 'unused';     for(var i=1; i<11 ; i++) {         // check if id exists first         var container = document.getelementbyid("q" + i);         if(container) {             // selected radio checkbox             var input = container.queryselector("input:checked");             // if there's 1 selected, save it's value             if(input) {                 answer[i] = input.value;             }             else {                 answer[i] = 0;             }         }     }     console.log(answer); } 

a working fiddle - http://jsfiddle.net/dtpljru1/