JSFiddle - React, Tailwind, and code Playground

HTML

<form name="invalidateForm" action="">Image Name:
    <br />
    <input id="imageName" type="text" name="imageName" value="">
    <br />
    <input class="btn" type="button" value="Generate URLs" id="gen">
    <input class="btn" type="reset">
    <br />
    <textarea id="icdnResults"></textarea>
</form>

JavaScript

var processForm = function () {
        var value = document.getElementById('imageName').value,
            html = '',
            imageTag = function (size) {
                return 'prefix ' + size + ' <<' + value + '>> suffix ' + size + "\n";
            },
            sizes = ['text', 'text 2', 'text 3'];


        for (var i = 0; i < sizes.length; i++) {
            html += imageTag(sizes[i]);
        }

        document.getElementById('icdnResults').value = html;
    };

    document.getElementById('gen').addEventListener('click', function () {
        processForm();
    }, false);