How to validate website address in javascript

gvalidate website address javascript by using Regular Expression in asp.net

Script block:
========

<script type="text/javascript">
        function ValidateWebsiteAddress() {
            var url = document.getElementById('<%=txtWebsiteAddress.ClientID %>').value;
     var urlIsValid =       ValidateWebAddress(url);      alert("Website Address is valid?:" +urlIsValid );
            return urlIsValid ;
        }
    

 function ValidateWebAddress(url) {
           var webSiteUrlExp = /^(([\w]+:)?\/\/)?(([\d\w]|%[a-fA-f\d]{2,2})+(:([\d\w]|%[a-fA-f\d]{2,2})+)?@)?([\d\w][-\d\w]{0,253}[\d\w]\.)+[\w]{2,4}(:[\d]+)?(\/([-+_~.\d\w]|%[a-fA-f\d]{2,2})*)*(\?(&?([-+_~.\d\w]|%[a-fA-f\d]{2,2})=?)*)?(#([-+_~.\d\w]|%[a-fA-f\d]{2,2})*)?$/;
           if (webSiteUrlExp.test(url)) {
               return true;
           }
           else {
               return false;
           }
       }


    </script>

.aspx File
======

  <asp:TextBox runat="server" ID="txtWebsiteAddress"></asp:TextBox>
  <asp:Button runat="server" OnClientClick="return ValidateWebsiteAddress()"  Text="Validate WebsiteAddress"/>
 

Demo:

=====