<html> <head> <script type="text/javascript" src="../../base.js"></script> <script type="text/javascript" src="../../dom.js"></script> <script type="text/javascript"> function test() { var elements = document.getElementsByClassName($('class-name').value); for (var i = 0; i < elements.length; i++) elements[i] = elements[i].id; alert(elements.join(', ')); return false; } </script> </head> <body> <div id="a" class="foo">a: foo</div> <div id="b" class="foo bar">b: foo, bar</div> <div id="c" class="bar">c: bar</div> <div id="d" class="bar baz">d: bar, baz</div> <div id="e" class="baz">e: baz</div> <div id="f" class="foo baz">f: foo, baz</div> <fieldset> <label for="class-name">Class name:</label> <input id="class-name" type="text" value="foo" /> <button onclick="return test()">Find</button> </fieldset> </body> </html>