gistfile1.txt

// <Name>UI layer shouldn't use directly DB types</Name>
warnif count > 0

// UI layer is made of types in namespaces using a UI framework
let uiTypes = Application.Namespaces.UsingAny(
   Assemblies.WithNameIn("PresentationFramework", "System.Windows", 
                         "System.Windows.Forms", "System.Web")
).ChildTypes()

// You can easily customize this line to define what are DB types.
let dbTypes = ThirdParty.Assemblies.WithNameIn("System.Data", "EntityFramework", 
                                               "NHibernate").ChildTypes()
              // Ideally even DataSet and associated, usage should be forbidden from UI layer: 
              // http://stackoverflow.com/questions/1708690/is-list-better-than-dataset-for-ui-layer-in-asp-net
              .Except(Types.WithNameIn("DataSet", "DataTable", "DataRow"))

from uiType in uiTypes.UsingAny(dbTypes)
let dbTypesUsed = dbTypes.Intersect(uiType.TypesUsed)
select new { uiType, dbTypesUsed }