10分钟搞定Linq to NHibernate(一)——环境篇

深碍√TFBOYSˉ_ 2021-11-29 13:34 142阅读 0赞

在微软发布C\# 3.0后， LINQ在项目中发挥了重要作用。作为3.0语言身份的象征之一，学习LINQ有为重要。而NHibernate作为运用最广的ORM框架之一，在大型项目中广受开发人员的青睐。前不久，[NHibernate Forge][]宣布[NHiberante Linq 1.0][]正式发布了（[参考][Link 1]）。 Linq to NHibernate有机的在NHibernate结合了Linq的查询功能，良好的把LINQ表达式转换为Criteria API。下面针对Linq to NHibernate做一个简单的Demo。

一、建立一个类名为NHibernateHelper的类

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] NHibernateHelper

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using NHibernate;
    using NHibernate.Cfg;
    using System.Web;
    
    namespace DBUtility
    {
        public sealed class NHibernateHelper
        {
            private const string CurrentSessionKey = "nhibernate.current_session";
            private static readonly ISessionFactory sessionFactory;
    
            static NHibernateHelper()
            {
                sessionFactory = new Configuration().Configure().BuildSessionFactory();
            }
    
            public static ISession GetCurrentSession()
            {
                HttpContext context = HttpContext.Current;
                ISession currentSession = context.Items[CurrentSessionKey] as ISession;
    
                if (currentSession == null)
                {
                    currentSession = sessionFactory.OpenSession();
                    context.Items[CurrentSessionKey] = currentSession;
                }
    
                return currentSession;
            }
    
            public static void CloseSession()
            {
                HttpContext context = HttpContext.Current;
                ISession currentSession = context.Items[CurrentSessionKey] as ISession;
    
                if (currentSession == null)
                {
                    // No current session
                    return;
                }
    
                currentSession.Close();
                context.Items.Remove(CurrentSessionKey);
            }
    
            public static void CloseSessionFactory()
            {
                if (sessionFactory != null)
                {
                    sessionFactory.Close();
                }
            }
        }
    
    }

二、使用sql2k自带的northwind数据中的Products表为，建立Products实体和对应的Products.hbm.xml文件加上Categories和Categories.hbm.xml。

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] Products

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] Products.hbm.xml

<?xml version="1.0" encoding="utf-8" ?>
    
    <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Domain" namespace="Domain.Entities">
        <class name="Domain.Entities.Products, Domain" table="Products">
            <id name="ProductID" column="ProductID" type="int" >
                <generator class="native" />
            </id>
        
            <property name="ProductName" column="ProductName" type="String" not-null="false"/>
            <property name="QuantityPerUnit" column="QuantityPerUnit" type="String" not-null="true"/>
            <property name="UnitPrice" column="UnitPrice" type="Decimal" not-null="true"/>
            <property name="UnitsInStock" column="UnitsInStock" type="Int16" not-null="true"/>
            <property name="UnitsOnOrder" column="UnitsOnOrder" type="Int16" not-null="true"/>
            <property name="ReorderLevel" column="ReorderLevel" type="Int16" not-null="true"/>
            <property name="Discontinued" column="Discontinued" type="Boolean" not-null="false"/>
        
        <many-to-one name="CategoriesEntitiy" column="CategoryID" class="Domain.Entities.Categories, Domain" />
        
        </class>
    </hibernate-mapping>

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] Categories

/*
    Class Library : Domain
    Author        : Liudong
    Create Date   : 2009-10-15
    */
    using System;
    using System.Collections;
    using System.Collections.Generic;
    using System.Runtime.Serialization;
    
    namespace Domain.Entities
    {
        #region Categories
        
        /// <summary>
        /// Entitiy:Categories object for NHibernate mapped table 
        /// </summary>
        [DataContract]
        public partial class Categories
        {
            #region CategoryID  
        
            /// <summary>
            /// Field:CategoryID 
            /// </summary>
            [DataMember]
            public virtual int? CategoryID { get; set; }
            
            #endregion   
            
            #region CategoryName  
        
            /// <summary>
            /// Field:CategoryName 
            /// </summary>
            [DataMember]
            public virtual string CategoryName { get; set; }
            
            #endregion   
            
            #region Description  
        
            /// <summary>
            /// Field:Description 
            /// </summary>
            [DataMember]
            public virtual string Description { get; set; }
            
            #endregion   
            
            #region Picture  
        
            /// <summary>
            /// Field:Picture 
            /// </summary>
            [DataMember]
            public virtual byte[] Picture { get; set; }
            
            #endregion   
            
        
            #region Products 
            
            /// <summary>
            /// ForeignKeyField:Products 
            /// </summary>
            [DataMember]
            public virtual IList<Products> ProductsList { get; set; }
            
            #endregion
        }
        #endregion
    }

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] Categories.hbm.xml

<?xml version="1.0" encoding="utf-8" ?>
    
    <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Domain" namespace="Domain.Entities">
        <class name="Domain.Entities.Categories, Domain" table="Categories">
            <id name="CategoryID" column="CategoryID" type="int" >
                <generator class="native" />
            </id>
            <property name="CategoryName" column="CategoryName" type="String" not-null="false"/>
            <property name="Description" column="Description" type="String" not-null="true"/>
            <property name="Picture" column="Picture" type="Byte[]" not-null="true"/>
        
        <bag name="ProductsList" inverse="true" lazy="true" cascade="all-delete-orphan">
          <key column="CategoryID" />
                <one-to-many  class="Domain.Entities.Products, Domain" />
            </bag>
        </class>
    </hibernate-mapping>

三、建立数据库访问层接口(IRepository)和其实现(Repository)，并引入程序集(Antlr3.Runtime.dll,Castle.Core.dll,Castle.DynamicProxy2.dll,Iesi.Collections.dll,log4net.dll,NHibernate.ByteCode.Castle.dll,NHibernate.dll,NHibernate.Linq.dll)。

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] IRepository

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    
    namespace RepositoryDao
    {
        public interface IRepository<T> where T : class
        {
            /// <summary>
            /// 返回IQueryable延迟加载集合
            /// </summary>
            /// <returns></returns>
            IQueryable<T> GetAll();
        }
    }

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] Repository

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    
    using NHibernate;
    using NHibernate.Linq;
    
    namespace RepositoryDao
    {
        public class Repository<T> : IRepository<T> where T : class
        {
            public IQueryable<T> GetAll()
            {
                ISession session = DBUtility.NHibernateHelper.GetCurrentSession();
                var result=from s in session.Linq<T>() select s;
                return result;
            }
        }
    }

四、建立一个ASP.NET MVC应用程序，同样引入上述的程序集。在Global.asax配置相应的MapRoute

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] Global.asax

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    using System.Web.Routing;
    using System.Text;
    
    namespace Linq2NHibernate
    {
        // Note: For instructions on enabling IIS6 or IIS7 classic mode, 
        // visit http://go.microsoft.com/?LinkId=9394801
    
        public class MvcApplication : System.Web.HttpApplication
        {
            public static void RegisterRoutes(RouteCollection routes)
            {
                routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
    
                routes.MapRoute(
                    "GetPage",                                              // Route name
                    "page/{pageId}/{pageSize}",                           // URL with parameters
                    new { controller = "Home", action = "GetPage", pageId = 1, pageSize = 10 }  // Parameter defaults
                );
    
                routes.MapRoute(
                    "GetOrderBy",                                              // Route name
                    "order",                           // URL with parameters
                    new { controller = "Home", action = "GetOrderBy" }  // Parameter defaults
                );
    
                routes.MapRoute(
                    "GetWhere",                                              // Route name
                    "where/{query}",                          // URL with parameters
                    new { controller = "Home", action = "GetWhere", query = "C" }  // Parameter defaults
                );
    
                routes.MapRoute(
                    "Default",                                              // Route name
                    "{controller}/{action}/{id}",                           // URL with parameters
                    new { controller = "Home", action = "Index", id = "" }  // Parameter defaults
                );
    
            }
    
            protected void Application_Start()
            {
                RegisterRoutes(RouteTable.Routes);
                //log4net配置信息
                log4net.Config.XmlConfigurator.Configure();//.DOMConfigurator.Configure();
            }
    
            protected void Application_Error(object sender, EventArgs e)
            {
                log4net.ILog logger = log4net.LogManager.GetLogger("Logger");
    
                if (Server.GetLastError() != null)
                {
                    Exception ex = Server.GetLastError().GetBaseException();
                    StringBuilder sb = new StringBuilder();
                    sb.Append(ex.Message);
                    sb.Append("\r\nSOURCE: " + ex.Source);
                    sb.Append("\r\nFORM: " + Request == null ? string.Empty : Request.Form.ToString());
                    sb.Append("\r\nQUERYSTRING: " + Request == null ? string.Empty : Request.QueryString.ToString());
                    sb.Append("\r\n引发当前异常的原因: " + ex.TargetSite);
                    sb.Append("\r\n堆栈跟踪: " + ex.StackTrace);
                    logger.Error(sb.ToString());
                    Server.ClearError();
                }
            }
        }
    }

在Web.config中配置hibernate和log4net

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] Web.config

<configuration>
        <configSections>
            <sectionGroup name="system.web.extensions" type="System.Web.Configuration.SystemWebExtensionsSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
                <sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
                    <section name="scriptResourceHandler" type="System.Web.Configuration.ScriptingScriptResourceHandlerSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
                    <sectionGroup name="webServices" type="System.Web.Configuration.ScriptingWebServicesSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
                        <section name="jsonSerialization" type="System.Web.Configuration.ScriptingJsonSerializationSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="Everywhere"/>
                        <section name="profileService" type="System.Web.Configuration.ScriptingProfileServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
                        <section name="authenticationService" type="System.Web.Configuration.ScriptingAuthenticationServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
                        <section name="roleService" type="System.Web.Configuration.ScriptingRoleServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
                    </sectionGroup>
                </sectionGroup>
            </sectionGroup>
    
        <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
        <sectionGroup name="common">
          <section name="logging" type="Common.Logging.ConfigurationSectionHandler, Common.Logging"/>
        </sectionGroup>
        
            <section name="hibernate-configuration" type="NHibernate.Cfg.ConfigurationSectionHandler, NHibernate"/>
        
        </configSections>
        <appSettings/>
        <connectionStrings>
            <add name="ApplicationServices" connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true" providerName="System.Data.SqlClient"/>
        </connectionStrings>
      
        <hibernate-configuration xmlns="urn:nhibernate-configuration-2.2">
            <session-factory name="Linq2NHibernate">
                <property name="connection.driver_class">NHibernate.Driver.SqlClientDriver</property>
                <property name="connection.connection_string">
            Server=(local);initial catalog=Northwind;Integrated Security=SSPI
          </property>
                <property name="adonet.batch_size">10</property>
                <property name="show_sql">false</property>
                <property name="dialect">NHibernate.Dialect.MsSql2000Dialect</property>
                <property name="use_outer_join">true</property>
                <property name="command_timeout">60</property>
                <property name="query.substitutions">true 1, false 0, yes 'Y', no 'N'</property>
                
                <property name="proxyfactory.factory_class">NHibernate.ByteCode.Castle.ProxyFactoryFactory, NHibernate.ByteCode.Castle</property>
                
                <mapping assembly="Domain"/>
            </session-factory>
        </hibernate-configuration>
    
      <log4net debug="true">
        <appender name="LogFileAppender" type="log4net.Appender.FileAppender">
          <param name="File" value="Logs\Application.log.txt"/>
          <param name="datePattern" value="MM-dd HH:mm"/>
          <param name="AppendToFile" value="true"/>
          <layout type="log4net.Layout.PatternLayout">
            <param name="ConversionPattern" value="%d [%t] %-5p %c [%x] - %m%n"/>
          </layout>
        </appender>
        <appender name="HttpTraceAppender" type="log4net.Appender.ASPNetTraceAppender">
          <layout type="log4net.Layout.PatternLayout">
            <param name="ConversionPattern" value="%d [%t] %-5p %c [%x] - %m%n"/>
          </layout>
        </appender>
        <appender name="EventLogAppender" type="log4net.Appender.EventLogAppender">
          <layout type="log4net.Layout.PatternLayout">
            <param name="ConversionPattern" value="%d [%t] %-5p %c [%x] - %m%n"/>
          </layout>
        </appender>
        <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
          <param name="File" value="Logs/Log.txt"/>
          <param name="AppendToFile" value="true"/>
          <param name="MaxSizeRollBackups" value="10"/>
          <param name="MaximumFileSize" value="100K"/>
          <param name="RollingStyle" value="Size"/>
          <param name="StaticLogFileName" value="true"/>
          <layout type="log4net.Layout.PatternLayout">
            <param name="ConversionPattern" value="%d [%t] %-5p %c [%x] - %m%n"/>
          </layout>
        </appender>
        <root>
          <level value="ALL"/>
          <appender-ref ref="RollingLogFileAppender"/>
        </root>
      </log4net>
      
        <system.web>

在HomeController加入如下方法

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] HomeController

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    using Domain.Entities;
    using RepositoryDao;
    
    namespace Linq2NHibernate.Controllers
    {
        [HandleError]
        public class HomeController : Controller
        {
            public ActionResult Index()
            {
                ViewData["Message"] = "Welcome to ASP.NET MVC!";
    
                return View();
            }
    
            public ActionResult About()
            {
                return View();
            }
    
            /// <summary>
            /// 获取所有
            /// </summary>
            /// <returns></returns>
            public ActionResult GetAll()
            {
                IRepository<Products> dao = new Repository<Products>();
                var products = dao.GetAll();
                
                ViewData["List"] = products;
                return View();
            }
    
            /// <summary>
            /// 更加id获取对象
            /// </summary>
            /// <param name="id"></param>
            /// <returns></returns>
            public ActionResult Get(int id)
            {
                IRepository<Products> dao = new Repository<Products>();
                var products = dao.GetAll().Where(w => w.ProductID == id).First<Products>();
                ViewData["Products"] = products;
                return View();
            }
    
            /// <summary>
            /// 分页
            /// </summary>
            /// <param name="pageId">页数</param>
            /// <param name="pageSize">每页数量</param>
            /// <returns></returns>
            public ActionResult GetPage(int pageId, int pageSize)
            {
                IRepository<Products> dao = new Repository<Products>();
                var products = dao.GetAll().Skip((pageId - 1) * pageSize).Take(pageSize);
    
                ViewData["List"] = products;
                return View();
            }
    
            /// <summary>
            /// 排序
            /// </summary>
            /// <returns></returns>
            public ActionResult GetOrderBy()
            {
                IRepository<Products> dao = new Repository<Products>();
                var products = dao.GetAll().OrderByDescending(o => o.ProductID);
                ViewData["List"] = products;
                return View();
            }
    
            /// <summary>
            /// 条件查询
            /// </summary>
            /// <param name="query"></param>
            /// <returns></returns>
            public ActionResult GetWhere(string query)
            {
                IRepository<Products> dao = new Repository<Products>();
                var products = dao.GetAll().Where(w => w.ProductName.StartsWith(query));
                ViewData["List"] = products;
                return View();
            }
        }
    }

html页面

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][] GetAll.aspx

<table>
            <tr>
                <td>ProductID</td>
                <td>ProductName</td>
                <td>QuantityPerUnit</td>
                <td>UnitPrice</td>
            </tr>
            <% foreach (Domain.Entities.Products item in ViewData["List"] as IEnumerable<Domain.Entities.Products>)
               { %>
            <tr>
                <td><%= item.ProductID %></td>
                <td><%= item.ProductName %></td>
                <td><%= item.QuantityPerUnit %></td>
                <td><%= item.UnitPrice %></td>
            </tr>
            <%} %>
        </table>

类似增加View：GetOrderBy，GetPage，GetWhere  
  
      至此Linq to NHibernate就实现了。  
  
      
      转自 刘东.net 博客  
      发表于 2009年10月16日临晨2点20，广州。

[代码下载][Link 2]

参考[http://mhinze.com/linq-to-nhibernate-in-10-minutes/][http_mhinze.com_linq-to-nhibernate-in-10-minutes]

[Linq To NHibernate环境下载][Linq To NHibernate]

转载于:https://www.cnblogs.com/FastForward/archive/2013/02/26/2933160.html

[NHibernate Forge]: http://nhforge.org/
[NHiberante Linq 1.0]: http://nhforge.org/blogs/nhibernate/archive/2009/07/26/nhibernate-linq-1-0-ga-released.aspx
[Link 1]: http://www.infoq.com/cn/news/2009/07/nhibernate-linq1.0-released
[ContractedBlock.gif]: https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif
[ExpandedBlockStart.gif]: /images/20211129/d52b352866fc4448a9b9085ba32aa64c.png
[Link 2]: http://files.cnblogs.com/GoodHelper/Linq2NHibernate.Step1.rar
[http_mhinze.com_linq-to-nhibernate-in-10-minutes]: http://mhinze.com/linq-to-nhibernate-in-10-minutes/
[Linq To NHibernate]: http://sourceforge.net/projects/nhibernate/files/