Here's the code from the previous post,

// The SharePoint portal URI of the root site.
var portalUrl = new Uri(Request.Url.GetLeftPart(UriPartial.Authority));
// The SharePoint sub site.
var portalSite = Request.QueryString["site"];
.
.
.
// Instantiate the SharePoint website object located at [portalUrl]/[portalSite].
SPWeb mySite = SPWebApplication.Lookup(portalUrl).Sites[portalSite].AllWebs[portalSite];