SharePoint Get Site Collections for Current User

Question

We have a SharePoint Web Application that has a number of Site Collections underneath 2 different managed paths (depts & offices) e.g

http://sharepoint.abc/depts/finance
http://sharepoint.abc/depts/isg
http://sharepoint.abc/offices/boston
http://sharepoint.abc/offices/chicago

When a user logs in they are presented with a list of the site collections they have read access to using the following c# code which is in the WebPart

 SPSecurity.RunWithElevatedPrivileges(delegate()
    {
        using (SPSite spSite = new SPSite(SPContext.Current.Site.Url))
        {
            foreach (SPSite site in spSite.WebApplication.Sites)
            {
                try
                {
                    var rootWeb = site.RootWeb;
                    if (rootWeb.DoesUserHavePermissions(SPContext.Current.Web.CurrentUser.LoginName, SPBasePermissions.ViewPages))
                    {
                        if (this.ValidSite(rootWeb.Url))
                        {
                            string url = GetRelativePath(rootWeb.Url);
                            allowedSites.Add(new SiteInfo(rootWeb.Title, url));
                        }
                    }
                }
                catch (Exception ex)
                {
                    this.Controls.Add(new LiteralControl("<br/>GetAllowedSites Error: " + ex.Message));
                }
            }

        }
    });

It works fine but in production it takes 20-seconds to load the webpart (we have 700 site collections across the 2 paths).

I've used caching to hold the list of their sites but once the cache expires it takes 20-seconds to regenerate itself.

Ideally what I want is to see what Site Collections a user can access using the User rather than iterating through all the Site Collections to see if the user has access to them. Can this be achieved???

Thanks

eaigs

Answer 1

Try to use SPWeb.GetSubwebsForCurrentUser method to get the subsites beneath the current website of which the current user is a member.