NHibernate開發入門

時間 2019-11-24

原文原文鏈接

首先，咱們瞭解一下ORM是什麼？
ORM指對象關係映射（英語：Object Relational Mapping，簡稱ORM，或O/RM，或O/R mapping），是一種程序技術，用於實現面向對象編程語言裏不一樣類型系統的數據之間的轉換。從效果上說，它實際上是建立了一個可在編程語言裏使用的「虛擬對象數據庫」。html

其次，咱們須要瞭解.NET領域ORM框架有哪些？
在.NET平臺下，關於數據持久層框架很是多，如下是主要的5種：
1．NHibernate
2．NBear
3．Castle ActiveRecord
4．iBATIS.NET
5．DAAB 微軟sql

使用過Java的朋友都不會對Hibernate陌生。因爲以前的Java經歷，因此我直接選擇NHibernate做爲ORM框架首選。那麼NHibernate是什麼？數據庫

NHibernate是一個面向.NET環境的對象/關係數據庫映射工具。對象/關係數據庫映射（object/relational mapping，ORM）這個術語表示一種技術，用來把對象模型表示的對象映射到基於SQL的關係模型數據結構中去。編程

下面，咱們作一個簡單的NHibernate Demo。建立項目WinForm窗體項目，命名爲CRMdemo，如下是解決方案截圖：session

解決方案項目截圖數據結構

獲取NHibernate

NHibernate下載地址app

https://sourceforge.net/projects/nhibernate/files/NHibernate/4.0.3.GA/NHibernate-4.0.3.GA-bin.zip/download框架

NHibernate項目地址編程語言

https://sourceforge.net/projects/nhibernate/ide

爲了方便，下載後將NHibernate-4.0.3.GA-bin.zip解壓縮至解決方案根目錄下

添加NHibernate Dll引用

添加引用

NHibernate-4.0.3.GA-bin\Required_Bins\NHibernate.dll

NHibernate-4.0.3.GA-bin\Required_Bins\Iesi.Collections.dll

NHibernate-4.0.3.GA-bin\Tests\log4net.dll

NHibernate-4.0.3.GA-bin\Tests\NHibernate.DomainModel.dll

NHibernate-4.0.3.GA-bin\Tests\nunit.framework.dll

配置hibernate.cfg.xml

複製NHibernate-4.0.3.GA-bin\Configuration_Templates\MSSQL.cfg.xml至bin\Debug下，重命名爲hibernate.cfg.xml，並作以下配置

<!-- This is the System.Data.dll provider for SQL Server -->
    <hibernate-configuration  xmlns="urn:nhibernate-configuration-2.2" >
    <session-factory name="CRMDemo.Hibernate">
    <property name="connection.driver_class">NHibernate.Driver.SqlClientDriver</property>
    <property name="connection.connection_string">
    Server=Your-PC\SQLEXPRESS;initial catalog=crm;Integrated Security=SSPI
    </property>
    <property name="dialect">NHibernate.Dialect.MsSql2008Dialect</property>
        <mapping assembly="CRMDemo"/>
    </session-factory>
    </hibernate-configuration>

在MSSQL中建立一張演示表employee

建立員工表employee

CREATE TABLE [dbo].[employee](
    [id] [int] IDENTITY(1,1) NOT NULL,
    [name] [nvarchar](50) NULL,
    [age] [nchar](10) NULL,
    [gender] [nchar](10) NULL,
    [email] [nvarchar](100) NULL,
    [phonenum] [nvarchar](50) NULL,
     CONSTRAINT [PK_employee] PRIMARY KEY CLUSTERED 
    (
    [id] ASC
    )WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF,  ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON)  ON [PRIMARY]
    ) ON [PRIMARY]

建立Employee.cs類

    public class Employee
    {
        public virtual int id { get; set; }
        public virtual string name { get; set; }
        public virtual int age { get; set; }
        public virtual string gender { get; set; }
        public virtual string email { get; set; }
        public virtual string phonenum { get; set; }
    }

建立映射文件Employee.hbm.xml，其中字段名稱必須和類屬性名稱一致，區分大小寫。

<?xml version="1.0" ?>
    <!--
    * By huiyaosoft.com
    * build date 2015-4-12 10:10
    -->
    <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" default-lazy="false">
    <class 
    name="CRMDemo.Employee, CRMDemo" 
    discriminator-value="0" table="employee" >
    <id 
    name="id" type="int"
    unsaved-value="null">
          <column name="id" length="4" sql-type="4" not-null="true" unique="true"
                  index="PK_employee"/>
          <generator class="native" />
    <!-- unsaved-value used to be null and generator was increment in h2.0.3 -->
    </id>
    <property name="name" type="String">
    <column name="name" length="50" sql-type="nvarchar" not-null="false"/>
    </property>
        <property name="email" type="String">
          <column name="email" length="50" sql-type="nvarchar" not-null="false"/>
        </property>
        <property name="gender" type="String">
          <column name="gender" length="10" sql-type="nchar" not-null="false"/>
        </property>
        <property name="phonenum" type="String">
          <column name="phonenum" length="50" sql-type="nvarchar" not-null="false"/>
        </property>
        <property name="age" type="int">
          <column name="age" length="4" sql-type="int" not-null="false"/>
        </property>
    </class>
 </hibernate-mapping>

設置Employee.hbm.xml爲嵌入的資源

增刪改查代碼

添加命名空間

using NHibernate;
using NHibernate.Cfg;

查詢操做，CreateQuery或CreateSqlQuery

Configuration cfg = new Configuration();
    cfg.Configure();
    ISessionFactory factory = cfg.BuildSessionFactory();
    ISession session = factory.OpenSession();
    IQuery query = session.CreateQuery("from Employee");
    IList<Employee> eList = query.List<Employee>();
    foreach (Employee item in eList)
    {
        this.textBox1.AppendText(string.Format("id:{0},name:{1},email:{2}\r\n", item.id, item.name, item.email));
    }
    //ISQLQuery query = session.CreateSQLQuery("select * from employee").AddEntity(typeof(Employee)); 
    //IList<Employee> eList = query.List<Employee>();
    //foreach (Employee item in eList)
    //{
    //    Console.WriteLine("id:{0},name:{1},email:{2}\r\n", item.id, item.name, item.email);
    //}
    session.Close();
    factory.Close();

增長操做session.Save(Entity)

Configuration cfg = new Configuration();
    cfg.Configure();
    ISessionFactory factory = cfg.BuildSessionFactory();
    ISession session = factory.OpenSession();
    ITransaction trans = session.BeginTransaction();
    Employee ee = new Employee();
    ee.age = 31;
    ee.name = "李四";
    ee.email = "zhang@163.com";
    ee.phonenum = "1358111111";
    ee.gender = "男";
    session.Save(ee);
    trans.Commit();
    session.Close();
    factory.Close();
    this.textBox1.AppendText("已增長一條記錄\r\n");

修改操做session.Save(Entity)

Configuration cfg = new Configuration();
    cfg.Configure();
    ISessionFactory factory = cfg.BuildSessionFactory();
    ISession session = factory.OpenSession();
    ITransaction trans = session.BeginTransaction();
    IQuery query = session.CreateQuery("from Employee where id = :id").SetString("id","1");
    IList<Employee> eList = query.List<Employee>();
    foreach (Employee item in eList)
    {
        this.textBox1.AppendText("查詢到一條記錄\r\n");
        this.textBox1.AppendText(string.Format("id:{0},name:{1},email:{2}\r\n", item.id, item.name, item.email));
        item.email = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss");
       session.Save(item);
    }
    trans.Commit();
    query = session.CreateQuery("from Employee where id = :id").SetString("id", "1");
    eList = query.List<Employee>();
    foreach (Employee item in eList)
    {
        this.textBox1.AppendText("修改後記錄\r\n");
        this.textBox1.AppendText(string.Format("id:{0},name:{1},email:{2}\r\n", item.id, item.name, item.email));
    }
   session.Close();
    factory.Close();

刪除操做session.Delete(Entity)

Configuration cfg = new Configuration();
    cfg.Configure();
    ISessionFactory factory = cfg.BuildSessionFactory();
    ISession session = factory.OpenSession();
    ITransaction trans = session.BeginTransaction();
    IQuery query = session.CreateQuery("from Employee where name = :name").SetString("name", "李四");
    IList<Employee> eList = query.List<Employee>();
    foreach (Employee item in eList)
    {
        this.textBox1.AppendText("查詢記錄\r\n");
        this.textBox1.AppendText(string.Format("id:{0},name:{1},email:{2}\r\n", item.id, item.name, item.email));
        session.Delete(item);
    }
    trans.Commit();
    query = session.CreateQuery("from Employee where name = :name").SetString("name", "李四");
    eList = query.List<Employee>();
    foreach (Employee item in eList)
    {
        this.textBox1.AppendText("刪除後記錄\r\n");
    }
    session.Close();
    factory.Close();