NHibernate入门

由于新公司用的是NHibernate数据库ORM, 所以也是在学习中,以前用Entity Framework,所以希望一步一步的学习。

要了解一个新技术,最经典的是从Hellow World!开始。

我们要完成的任务:

  • 一、使用Visual Studio 2015 建立一个控制台项目
  • 二、使用NuGet安装NHibernate
  • 三、下载NHibernate(上面用Nuget安装了,为什么还要下载呢?因为下载包里有个文件要用到,给VS智能感知用的,在做表配置映射的时候会智能提示)
  • 四、添加一个本地数据库文件,用以建测试数据库用
  • 五、配置NHibernate,包括:
  • 六、编写代码,读取数据库记录
  • 七、对数据的CRUD操作。
  • 八、数据库改为MySQL,目前公司在用MySQL

下面我们就一步一步安装上面的步骤完成任务


一、新建控制台项目:NHFirstDemo

二、使用NuGet安装NHibernate

安装完成后的类库引用多了2个项,其他没有变。(多个packages.config,Nuget配置文件)

三、下载NHibernate(上面用Nuget安装了,为什么还要下载呢?因为下载包里有个文件要用到,给VS智能感知用的,在做表配置映射的时候会智能提示)

现在地址:http://nhibernate.info/ 

安装包如下:

解压后,里面很多文件

其中Required_Bins 包括我们需要的文件

四、添加一个本地数据库文件 DemoDB,用以建测试数据库用

 创建表User,3个字段,id主键,标识,不为空。Name50个字符串可空,Age 整形,可空,建议规范命名,首字母大写,字符串用nvarchar 类型不会有乱码出现

 随便插入几条测试数据:

 五、配置NHibernate,包括:

创建映射文件,一个实体一个文件,User.hbm.xml,双击打开该文件,然后在空白处右击选择属性导入智能提示文件

 看看,有智能提示了

User.hbm.xml 文件内容:

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" schema="NHFirstDemo" namespace="NHFirstDemo.NHFirstDemo">
  <class name="User">
    <id name="Id" generator="hilo" />
    
    <property name="Name" />
    <property name="Age" />

  </class>
</hibernate-mapping>

再新加一个实体类(POCO)文件 User.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace NHFirstDemo
{
    public class User
    {
        public virtual int Id { get; set; }
        public virtual string Name { get; set; }
        public virtual int Age { get; set; }
    }
}

=====================================================================================================

换一个类来做示例 

Customer.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace NHibernateDemoApp
{
    public class Customer
    {
        public virtual int Id { get; set; }
        public virtual string FirstName { get; set; }
        public virtual string LastName { get; set; }
        public virtual double AverageRating { get; set; }
        public virtual int Points { get; set; }
        public virtual bool HasGoldStatus { get; set; }
        public virtual DateTime MemberSince { get; set; }
        public virtual CustomerCreditRating  CreditRating { get; set; }
        public virtual string Street { get; set; }
        public virtual string City { get; set; }
        /// <summary>
        /// 省份
        /// </summary>
        public virtual string Province { get; set; }
        public virtual string Country { get; set; }

    }
    public enum CustomerCreditRating
    {
        /// <summary>
        /// 卓越的;极好的;杰出的
        /// </summary>
        Excellent,

        /// <summary>
        /// 非常棒
        /// </summary>
        VeryVeryGood,

        /// <summary>
        /// 很好
        /// </summary>
        VeryGood,

        /// <summary>
        /// 好
        /// </summary>
        Good,

        /// <summary>
        /// 一般
        /// </summary>
        Neutral,
        /// <summary>
        /// 差
        /// </summary>
        Poor,

        /// <summary>
        /// 惨不忍睹
        /// </summary>
        Terrible
    }
}

对应的映射文件 Customer.hbm.xml

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="NHibernateDemoApp" namespace="NHibernateDemoApp">
  <class name="Customer" table="Customer">
    <id name="Id">
      <generator class="native" />
    </id>
    <property name="FirstName" not-null="true" />
    <property name="LastName" not-null="true" />
    <property name="AverageRating" />
    <property name="Points" />
    <property name="HasGoldStatus" />
    <property name="MemberSince" />
    <property name="CreditRating" type="CustomerCreditRating" />
    <property name="Street" />
    <property name="City" />
    <property name="Province" />
    <property name="Country" />
  </class>
</hibernate-mapping>
  • 注意hibernate-mapping的assembly、namespace属性要填写正确
  • class的name属性表示类名,table是映射的表名,如果类名称和表名称相同,可以省略table属性
  • property的name属性是类的属性名,如果类属性名和表的列名相同,可以省略column属性
  • property的type属性表示.net类属性映射的NHibernate数据类型。如果是int、bool、double这样的.net基础数据类型,则可以省略
  • property的type属性如果是DateTime、string,也可以省略
  • property的not-null属性对应关系表的列的nullable属性,默认值是false。因此,如果允许为空,则可以省略
  • id表示主键,name为主键名,<generator class="native"/>表示数据表的主键按简单Identity的自增算法生成新记录主键值(NHibernate提供了多种主键值生成算法,这里只用最简单的Identity算法)
  • 文件名必须以.hbm.xml结尾 

  

连接配置数据库

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using NHibernate.Cfg;
using NHibernate.Dialect;
using NHibernate.Driver;
using System.Reflection;

namespace NHibernateDemoApp
{
    class Program
    {
        static void Main(string[] args)
        {
            var cfg = new Configuration();//Configuration类对象相当于ADO.Net的Connection对象,但是他包含更丰富的配置信息。

            //调用cfg.DataBaseIntegration方法进行配置,这里配置了:数据库连接字符串、使用连接的Driver类SqlClientDriver和使用Dialect类MsSql2008Dialect
            cfg.DataBaseIntegration(x =>
            {
                x.ConnectionString = "Data Source=localhost;Initial Catalog=NHibernateDemoDB;Integrated Security=True;Connect Timeout=15;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False";
                x.Driver<SqlClientDriver>();
                x.Dialect<MsSql2008Dialect>();
            });

            cfg.AddAssembly(Assembly.GetExecutingAssembly());//告诉NHibernate去哪里找xml映射文件信息
            var sefact = cfg.BuildSessionFactory();//SessionFactory和Session是NHibernate的基础类,SessionFactory编译所有的元数据,产生Session。Session封装了所有的NHibernate方法
            using (var session = sefact.OpenSession())
            {
                using (var tx = session.BeginTransaction())
                {
                    //
                    tx.Commit();
                    Console.WriteLine("Well Done");
                }
                Console.ReadLine();
            }
        }
    }
}

改进上面的操作方法

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using NHibernate.Cfg;
using NHibernate.Dialect;
using NHibernate.Driver;
using System.Reflection;
using NHibernate;

namespace NHibernateDemoApp
{
    class Program
    {
        private static ISessionFactory _sessionFactory;

        public static ISessionFactory SessionFactory
        {
            get
            {
                //SessionFactory的创建很占用系统资源,一般在整个应用程序中只创建一次。因此,这里通过判断if (_sessionFactory == null)实现一个最简单的单例模式。
                if (_sessionFactory == null) 
                {
                    var cfg = new Configuration();
                    cfg.DataBaseIntegration(x =>
                    {
                        x.ConnectionString = "Data Source=localhost;Initial Catalog=NHibernateDemoDB;Integrated Security=True;Connect Timeout=15;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False";
                        x.Driver<SqlClientDriver>();
                        x.Dialect<MsSql2008Dialect>();
                    });
                    cfg.AddAssembly(Assembly.GetExecutingAssembly());
                    _sessionFactory = cfg.BuildSessionFactory();
                }
                return _sessionFactory;
            }
        }

        private static IList<Customer> GetAll()
        {
            using (var session = SessionFactory.OpenSession())
            {
                IList<Customer> list = session.CreateCriteria<Customer>().List<Customer>();
                return list;
            }
        }

        private static Customer GetById(int id)
        {
            using (var session = SessionFactory.OpenSession())
            {
                Customer customer = session.Get<Customer>(id);
                return customer;
            }
        }

        /// <summary>
        /// 新增客户
        /// </summary>
        /// <param name="customer">客户对象</param>
        /// <returns>插入后的客户ID</returns>
        private static int Insert(Customer customer)
        {
            using (var session = SessionFactory.OpenSession())
            {
                var identifier = session.Save(customer);//插入新记录,返回新纪录主键值
                session.Flush();//增删改操作完成之后需要调用session.Flush()方法,将对象持久化写入数据库。如果不调用此方法,方法结束后修改记录不能写入到数据库
                return Convert.ToInt32(identifier);
            }
        }

        private static void Update(Customer customer)
        {
            using (var session = SessionFactory.OpenSession())
            {
                session.SaveOrUpdate(customer);//如果被调用的Customer对象在数据库里不存在(新记录),则插入新记录,否则修改该记录
                session.Flush();
            }
        }

        private static void Delete(int id)
        {
            using (var session = SessionFactory.OpenSession())
            {
                var customer = session.Load<Customer>(id);
                session.Delete(customer);//传入Customer对象进行删除
                session.Flush();
            }
        }
        static void Main(string[] args)
        {
            #region 原始链接数据库方法
            /*
            var cfg = new Configuration();//Configuration类对象相当于ADO.Net的Connection对象,但是他包含更丰富的配置信息。

            //调用cfg.DataBaseIntegration方法进行配置,这里配置了:数据库连接字符串、使用连接的Driver类SqlClientDriver和使用Dialect类MsSql2008Dialect
            cfg.DataBaseIntegration(x =>
            {
                x.ConnectionString = "Data Source=localhost;Initial Catalog=NHibernateDemoDB;Integrated Security=True;Connect Timeout=15;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False";
                x.Driver<SqlClientDriver>();
                x.Dialect<MsSql2008Dialect>();
            });

            cfg.AddAssembly(Assembly.GetExecutingAssembly());//告诉NHibernate去哪里找xml映射文件信息
            var sefact = cfg.BuildSessionFactory();//SessionFactory和Session是NHibernate的基础类,SessionFactory编译所有的元数据,产生Session。Session封装了所有的NHibernate方法
            using (var session = sefact.OpenSession())
            {
                using (var tx = session.BeginTransaction())
                {
                    //
                    tx.Commit();
                    Console.WriteLine("Well Done");
                }
                Console.ReadLine();
            }
            */
            #endregion


            Customer newCustomer = CreateCustomer();
            int customerId = Insert(newCustomer);
            Console.WriteLine("新客户ID:{0}", customerId);

            IList<Customer> list = GetAll();
            Console.WriteLine("客户列表数量:{0}", list.Count);
            foreach (var item in list)
            {
                Console.WriteLine("{0} {1}", item.FirstName, item.LastName);
            }

            var customer = GetById(customerId);
            Console.WriteLine("GetById: {0} {1}", customer.FirstName, customer.LastName);

            customer.LastName = "Chen";
            Update(customer);
            var updatedCustomer = GetById(customerId);
            Console.WriteLine("updated: {0} {1}", updatedCustomer.FirstName, updatedCustomer.LastName);

            Delete(customerId);
            var existedCustomer = GetById(customerId);
            Console.WriteLine("after deleted: existing: {0}", existedCustomer != null);

            Console.ReadLine();

        }

        //示例数据
        private static Customer CreateCustomer()
        {
            var customer = new Customer
            {
                FirstName = "Daniel",
                LastName = "Tang",
                Points = 100,
                HasGoldStatus = true,
                MemberSince = new DateTime(2012, 1, 1),
                CreditRating = CustomerCreditRating.Good,
                AverageRating = 42.42424242,
                Street = "123 Somewhere Avenue",
                City = "Nowhere",
                Province = "Alberta",
                Country = "Canada"
            };
            return customer;
        }



    }
}

  

 

持续更新,这只是个开始....
http://www.codeproject.com/Articles/830326/CRUD-Operations-with-ASP-NET-Web-API-using-FluentN 

http://www.codeproject.com/Articles/891056/Automatic-Table-Generation-in-any-database-by-NHib

原文地址:https://www.cnblogs.com/wanghaibin/p/5344320.html