utility method for resolving a ListFormWebPart on a custom page

utilities.cs

// in code behind (null checking/exception catching omitted for clarity)
var listItemId = int.Parse(Request["ID"]);
Utilities.ResolveListFormWebPart("MyListName", listItemId, MyListFormWebPart);

// in utilities class
internal static void ResolveListFormWebPart(string listName, int listItemId, ListFormWebPart listFormWebPart)
{
    using (var site = new SPSite(SPContext.Current.Web.Url))
    using (var web = site.OpenWeb())
    {
        var theList = web.Lists[listName];
        if (theList == null)
        {
            throw new NullReferenceException(string.Format("The specified list '{0}' does not exist in the site '{1}'.", listName, SPContext.Current.Web.Url));
        }

        listFormWebPart.ListId = theList.ID;
        listFormWebPart.ListItemId = listItemId;
    }
}