JS function for validating internet URL

I am posting this since most of the Regular Expressions I got from the NET where not working on
non-IE browsers..

function validate()
{

if (document.Form1.TextBox1.value!='')
{
var urlRegxp = /(ftp|http|https):\/\/(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?/;
var url = document.Form1.TextBox1.value
if(urlRegxp.test(url) != true)
{
alert('Please enter a valid External URL');
document.Form1.TextBox1.focus();
return false;
}
}
}

Cheers
Rajesh Sivaraman.

Setting focus to a textbox from codebehind

Dim fun As String

fun = fun & "Script language='javascript'" & vbCrLf

fun = fun & "function setFocus() {" & vbCrLf

fun = fun & "document.getElementById('txtDomainName').focus();" & vbCrLf

fun = fun & "}" & vbCrLf

fun = fun & "window.onload = setFocus;" & vbCrLf

fun = fun & "/Script" & vbCrLf

RegisterClientScriptBlock("Focus", fun)


On the 2nd and 7th lines above provide angle brackets "<" or ">" accordingly as blogger is not allowing me to post like as it is ;-)