<ExtensionAttribute()>
Public Overloads Shared Function Count( _
   ByVal source As IQueryable, _
   ByVal predicateDescription As IPredicateDescription _
) As Integer

Dim source As IQueryable
Dim predicateDescription As IPredicateDescription
Dim value As Integer
 
value = QueryableExtensions.Count(source, predicateDescription)

[ExtensionAttribute()]
public static int Count( 
   IQueryable source,
   IPredicateDescription predicateDescription
)

[ExtensionAttribute()]
public:
static int Count( 
   IQueryable^ source,
   IPredicateDescription^ predicateDescription
) 

var mgr1 = new DomainModelEntityManager();

var entityType = typeof(Customer);
var baseQuery = EntityQuery.Create(entityType);
var pd = new PredicateDescription(Customer.EntityPropertyNames.Country, FilterOperator.IsEqualTo, "UK");
var count = baseQuery.Count(pd);