How to get all elements inside "div" that starts with a known text

Question

I have a div element in an HTML document.

I would like to extract all elements inside this div with id attributes starting with a known string (e.g. "q17_").

How can I achieve this using JavaScript ?

If needed, for simplicity, I can assume that all elements inside the div are of type input or select.

Answer 1

var matches = []; var searchEles = document.getElementById("myDiv").children; for(var i = 0; i < searchEles.length; i++) {     if(searchEles[i].tagName == 'SELECT' || searchEles.tagName == 'INPUT') {         if(searchEles[i].id.indexOf('q1_') == 0) {             matches.push(searchEles[i]);         }     } } 

Once again, I strongly suggest jQuery for such tasks:

$("#myDiv :input").hide(); // :input matches all input elements, including selects 

Answer 2

Option 1: Likely fastest (but not supported by some browsers if used on Document or SVGElement) :

var elements = document.getElementById('parentContainer').children; 

Option 2: Likely slowest :

var elements = document.getElementById('parentContainer').getElementsByTagName('*'); 

Option 3: Requires change to code (wrap a form instead of a div around it) :

// Since what you're doing looks like it should be in a form... var elements = document.forms['parentContainer'].elements;  var matches = [];  for (var i = 0; i < elements.length; i++)     if (elements[i].value.indexOf('q17_') == 0)         matches.push(elements[i]);