How to avoid this ['<', "'", '(', ')', '{', '}', '[', ']', '*', '+', '/"', ',', ';', '%7B', '/*', '@', '='] character in url request for avoid url hacking?

Hi 
I have develop an web application and some hacker hack my application using some url so i develope javascript for this 
<script type="text/javascript">
function secureUrl() {
var loc = window.location.href //alert(loc) var array = ['<', "'", '(', ')', '{', '}', '[', ']', '*', '+', '/"', ',', ';', '%7B', '/*', '@', '=']
for (var i = 0; i <= array.length; i++) { if (loc.indexOf(array[i]) === -1) { //textsizer(loc.indexOf(array[i])) //ProcessKeyPressed(loc.indexOf(array[i])) } else { window.location = "http://abc.abc.intranet/" } } }
</script>

and its working fine but its not working for character < when its give me error which is 
HTTP Error 400 - Bad Request. when i run first time the page ...