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c#nhibernateicriteria

What's the difference/advantages between ICriteria and ICriterion in nHibernate?

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?

Solution

  • 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.