Question

Bit of a newbie question as Im getting started with nHibernate.

What’s the difference between NHibernate.Criterion.ICriterion and NHibernate.ICriteria classes and which should I use for simple “where field=value” type filtering?

Answer 1

An ICriteria is used to represent a query.
You can add ICriterions to this ICriteria to express filters.

For instance:

ICriteria crit = session.CreateCriteria (typeof(Person));

crit.Add (NHibernate.Criterion.Expression.Eq("Name", "somename"));

Or, as the documentation states:

ICriterion: An object oriented
representation of a query criterion
that may be used as a constraint in an
ICriteria query

ICriteria: a simplified API for
retrieving entities by composing
NHibernate.Criterion.Expression
objects.