JSFiddle - React, Tailwind, and code Playground
HTML
<h1>matches</h1>
<div id="matches"></div>
<h1>non matches</h1>
<div id="nonmatches"></div>
JavaScript
var images = [
"sm234234.gif"
, "lg234 23423.jpg"
, "xl234234.gif"
, "dss23 4234.gif"
, "dsh2432423.jpg"
];
for(var i in images){
if(images[i].search(/(sm|lg|xl)/i) == 0){
jQuery("#matches").append(images[i] + "<br>");
}else{
jQuery("#nonmatches").append(images[i] + "<br>");
}
}