How to pass multiple querystring in DotNetNuke

//SET
string QueryString1 = string.Format("FirstName={0}", "IT Headway");

string QueryString2 = string.Format("LastName={0}", "Technology");
string QueryString3 = string.Format("Website={0}", "http://www.itheadway.com");
string[] arrOfStrings = { QueryString1, QueryString2, QueryString3 };
string navurl = DotNetNuke.Common.Globals.NavigateURL(4, "", arrOfStrings);
HyperLink1.NavigateUrl = navurl;

//Get
if (Request.QueryString["FirstName"] != null && Request.QueryString["LastName"] != null && Request.QueryString["Website"] != null)

{
Label1.Text = Request.QueryString["FirstName"].ToString();
Label1.Text += Request.QueryString["LastName"].ToString();
Label1.Text += Environment.NewLine + Request.QueryString["Website"].ToString();
}