在本章中，我们将介绍人们将使用的另一个常见API是NHibernate LINQ提供程序.它通过ISession上的扩展方法和签名进行访问是 Query< T> .使用LINQ&minus时有两种语法;
查询链接语法
查询理解语法
查询链接语法
您可以使用方法链语法访问数据库中的任何记录，如下所示以下程序.
var customer = session.Query() .Where(c => c.FirstName == "Laverne")
你可以看到我们有查询，还有WHERE子句，你可以有额外的WHERE子句和类似的select子句.
这是一种标准的方法链语法，你可以在普通的LINQ中使用.
LINQ to Objects或LINQ to SQL，您可能熟悉的任何其他LINQ提供程序.
让我们看一个简单的例子，我们将检索名字为Laverne的客户.现在我们可能有多个客户的名字是Laverne，所以我们只检索第一个.
using System; using System.Data; using System.Linq; using System.Reflection; using HibernatingRhinos.Profiler.Appender.NHibernate; using NHibernate.Cfg; using NHibernate.Criterion; using NHibernate.Dialect; using NHibernate.Driver; using NHibernate.Linq;namespace NHibernateDemo { internal class Program { private static void Main() { var cfg = ConfigureNHibernate(); var sessionFactory = cfg.BuildSessionFactory(); using(var session = sessionFactory.OpenSession()) using(var tx = session.BeginTransaction()) { var customer = session.Query() .Where(c => c.FirstName == "Laverne").First(); Console.WriteLine(customer); tx.Commit(); } Console.WriteLine("Press to exit..."); Console.ReadLine(); } private static Configuration ConfigureNHibernate() { NHibernateProfiler.Initialize(); var cfg = new Configuration(); cfg.DataBaseIntegration(x => { x.ConnectionStringName = "default"; x.Driver(); x.Dialect(); x.IsolationLevel = IsolationLevel.RepeatableRead; x.Timeout = 10; x.BatchSize = 10; }); cfg.SessionFactory().GenerateStatistics(); cfg.AddAssembly(Assembly.GetExecutingAssembly()); return cfg; } } } 现在编译并执行上面的代码时，您将看到以下输出./p>
Laverne Hegmann (4e97c816-6bce-11e1-b095-6cf049ee52be) Points: 74 HasGoldStatus: True MemberSince: 4/4/2009 12:00:00 AM (Utc) CreditRating: Neutral AverageRating: 0 Orders: Order Id: 4ea14d96-6bce-11e1-b095-6cf049ee52be Order Id: 4ea14d96-6bce-11e1-b096-6cf049ee52be Order Id: 4ea14d96-6bce-11e1-b097-6cf049ee52be Order Id: 4ea14d96-6bce-11e1-b098-6cf049ee52bePressto exit...
查询理解语法
还有查询理解语法，看起来更像SQL使用from，where和select关键字.
所以让我们看看同一个例子，但是这次我们使用LINQ comprehensions语法，它看起来更像SQL，如图所示以下程序.
using System; using System.Data; using System.Linq; using System.Reflection; using HibernatingRhinos.Profiler.Appender.NHibernate; using NHibernate.Cfg; using NHibernate.Criterion; using NHibernate.Dialect; using NHibernate.Driver; using NHibernate.Linq;namespace NHibernateDemo { internal class Program { private static void Main() { var cfg = ConfigureNHibernate(); var sessionFactory = cfg.BuildSessionFactory(); using(var session = sessionFactory.OpenSession()) using(var tx = session.BeginTransaction()) { var customer = (from c in session.Query() where c.FirstName == "Laverne" select c).First(); Console.WriteLine(customer); tx.Commit(); } Console.WriteLine("Press to exit..."); Console.ReadLine(); } private static Configuration ConfigureNHibernate() { NHibernateProfiler.Initialize(); var cfg = new Configuration(); cfg.DataBaseIntegration(x => { x.ConnectionStringName = "default"; x.Driver(); x.Dialect(); x.IsolationLevel = IsolationLevel.RepeatableRead; x.Timeout = 10; x.BatchSize = 10; }); cfg.SessionFactory().GenerateStatistics(); cfg.AddAssembly(Assembly.GetExecutingAssembly()); return cfg; } } } 现在让我们再次运行此应用程序，您将看到以下输出.
Laverne Hegmann (4e97c816-6bce-11e1-b095-6cf049ee52be) Points: 74 HasGoldStatus: True MemberSince: 4/4/2009 12:00:00 AM (Utc) CreditRating: Neutral AverageRating: 0 Orders: Order Id: 4ea14d96-6bce-11e1-b095-6cf049ee52be Order Id: 4ea14d96-6bce-11e1-b096-6cf049ee52be Order Id: 4ea14d96-6bce-11e1-b097-6cf049ee52be Order Id: 4ea14d96-6bce-11e1-b098-6cf049ee52bePressto exit...
让我们看看另一个例子，我们将检索所有那些FirstName以字母H开头的客户.
using System; using System.Data; using System.Linq; using System.Reflection; using HibernatingRhinos.Profiler.Appender.NHibernate; using NHibernate.Cfg; using NHibernate.Criterion; using NHibernate.Dialect; using NHibernate.Driver; using NHibernate.Linq;namespace NHibernateDemo { internal class Program { private static void Main() { var cfg = ConfigureNHibernate(); var sessionFactory = cfg.BuildSessionFactory(); using(var session = sessionFactory.OpenSession()) using(var tx = session.BeginTransaction()) { var customers = session.Query() .Where(c =< c.FirstName.StartsWith("H")); foreach (var customer in customers.ToList()) { Console.WriteLine(customer); } tx.Commit(); } Console.WriteLine("Press to exit..."); Console.ReadLine(); } private static Configuration ConfigureNHibernate() { NHibernateProfiler.Initialize(); var cfg = new Configuration(); cfg.DataBaseIntegration(x => { x.ConnectionStringName = "default"; x.Driver(); x.Dialect(); x.IsolationLevel = IsolationLevel.RepeatableRead; x.Timeout = 10; x.BatchSize = 10; }); cfg.SessionFactory().GenerateStatistics(); cfg.AddAssembly(Assembly.GetExecutingAssembly()); return cfg; } } } 同样，查询理解语法类似于以下程序.
using System; using System.Data; using System.Linq; using System.Reflection; using HibernatingRhinos.Profiler.Appender.NHibernate; using NHibernate.Cfg; using NHibernate.Criterion; using NHibernate.Dialect; using NHibernate.Driver; using NHibernate.Linq;namespace NHibernateDemo { internal class Program { private static void Main() { var cfg = ConfigureNHibernate(); var sessionFactory = cfg.BuildSessionFactory(); using(var session = sessionFactory.OpenSession()) using(var tx = session.BeginTransaction()) { var customers = from c in session.Query() where c.FirstName.StartsWith("H") select c; foreach (var customer in customers.ToList()) { Console.WriteLine(customer); } tx.Commit(); } Console.WriteLine("Press to exit..."); Console.ReadLine(); } private static Configuration ConfigureNHibernate() { NHibernateProfiler.Initialize(); var cfg = new Configuration(); cfg.DataBaseIntegration(x => { x.ConnectionStringName = "default"; x.Driver(); x.Dialect(); x.IsolationLevel = IsolationLevel.RepeatableRead; x.Timeout = 10; x.BatchSize = 10; }); cfg.SessionFactory().GenerateStatistics(); cfg.AddAssembly(Assembly.GetExecutingAssembly()); return cfg; } } } 让我们再次运行此应用程序，您将看到所有客户，其名字开头字母H.
Herman Crooks (4ead3480-6bce-11e1-b15c-6cf049ee52be) Points: 74 HasGoldStatus: True MemberSince: 12/3/2010 12:00:00 AM (Utc) CreditRating: Neutral AverageRating: 0 Orders: Order Id: 4ead3480-6bce-11e1-b15d-6cf049ee52be Order Id: 4ead3480-6bce-11e1-b15e-6cf049ee52be Order Id: 4ead3480-6bce-11e1-b15f-6cf049ee52be Order Id: 4ead3480-6bce-11e1-b160-6cf049ee52be Order Id: 4ead3480-6bce-11e1-b161-6cf049ee52be Order Id: 4ead3480-6bce-11e1-b162-6cf049ee52be Order Id: 4ead3480-6bce-11e1-b163-6cf049ee52beHudson Bins (4ec03f80-6bce-11e1-b2b7-6cf049ee52be) Points: 56 HasGoldStatus: False MemberSince: 10/20/2008 12:00:00 AM (Utc) CreditRating: Terrible AverageRating: 0 Orders: Order Id: 4ec03f80-6bce-11e1-b2b8-6cf049ee52be Order Id: 4ec03f80-6bce-11e1-b2b9-6cf049ee52be Order Id: 4ec03f80-6bce-11e1-b2ba-6cf049ee52be Order Id: 4ec03f80-6bce-11e1-b2bb-6cf049ee52be Order Id: 4ec03f80-6bce-11e1-b2bc-6cf049ee52be Order Id: 4ec03f80-6bce-11e1-b2bd-6cf049ee52be Order Id: 4ec03f80-6bce-11e1-b2be-6cf049ee52be Order Id: 4ec03f80-6bce-11e1-b2bf-6cf049ee52beHettie Feest (4ec50240-6bce-11e1-b300-6cf049ee52be) Points: 82 HasGoldStatus: False MemberSince: 4/10/2009 12:00:00 AM (Utc) CreditRating: Neutral AverageRating: 0 Orders: Order Id: 4ec50240-6bce-11e1-b301-6cf049ee52be Order Id: 4ec50240-6bce-11e1-b302-6cf049ee52be Order Id: 4ec50240-6bce-11e1-b303-6cf049ee52bePressto exit...