SO jQuery Fiddle

Test Fiddle mainly for SO Questions jQuery 1.4.3, UI 1.8.5

by thanhansoft

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.5/themes/ui-lightness/jquery-ui.css">
<input type="hidden" value="/TEST/Name?3" />

JavaScript

var val = "tab_en";
var myString = val.substr(val.indexOf("_") + 1)
alert(myString);