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