How to redirect page?

Suppose I am browsing Orders.aspx without login to that website using any credentials, web authenticator treated me as ? user so it redirect me to login page back. After login successfully how can I redirect to my past location from which this redirectional process occurred?

var redirectUrl = Request.QueryString["ReturnUrl"]; 
 
if (redirectUrl != null) 
{ 
    Response.Redirect(redirectUrl, false); 
} 
else 
{ 
    Response.Redirect("Home.aspx"); 
}