NHibernate&&Linq简单的CRUD操作

      因为最近在做一些有关数据库方面的开发，其实，说白了，就是对数据库的CRUD操作，写了n多的存储过程，倒不是说存储过程多难，关键是在后期的维护方面有点头疼，没办法，研究一下ORM吧。

      下面分别是用NHibernate和Linq实现的简单的CRUD操作，当是一开始的练练手（开关环境：VS08+SQL2000）。

       ①：NHibernate

       不管三七二十一，先看看实体类吧。（数据库代码省略，映射文件对应着表结构）  

代码

     public   class  User
    {
         #region  构造函数
         ///   <summary>
         ///  用户信息
         ///   </summary>
         public  User() { }
         #endregion

         #region  属性

         private   int  userID;
         ///   <summary>
         ///  用户ID
         ///   </summary>
         public   virtual   int  UserID
        {
             get
            {
                 return  userID;
            }
             set
            {
                userID  =  value;
            }
        }

         private   string  userName;
         ///   <summary>
         ///  用户姓名
         ///   </summary>
         public   virtual   string  UserName
        {
             get
            {
                 return  userName;
            }
             set
            {
                userName  =  value;
            }
        }

         private   string  userPwd;
         ///   <summary>
         ///  用户密码
         ///   </summary>
         public   virtual   string  UserPwd
        {
             get
            {
                 return  userPwd;
            }
             set
            {
                userPwd  =  value;
            }
        }

         private   int  userAge;
         ///   <summary>
         ///  用户年龄
         ///   </summary>
         public   virtual   int  UserAge
        {
             get
            {
                 return  userAge;
            }
             set
            {
                userAge  =  value;
            }
        }
         #endregion
    }

 

      这里用的NHibernate是NHibernate-2.1.2.GA-bin,映射文件如下（注意映射文件中nh的版本号）：

代码

<? xml version = " 1.0 "  encoding = " utf-8 "   ?>
< hibernate - mapping xmlns = " urn:nhibernate-mapping-2.2 "   >
   < class  name = " NHUser.User,NHUser "  table = " UserInfo " > //NHUser为命名空间、UserInfo为数据表名
     < id name = " UserID "  type = " Int32 "  unsaved - value = " null " >
       < column name = " UserID "  length = " 4 "  sql - type = " int "  not - null = " true "  unique = " true "  index = " PK_UserInfo " />
       < generator  class = " native " />
     </ id >
     < property name = " UserName "  type = " String " >
       < column name = " UserName "  length = " 50 "  sql - type = " nvarchar "  not - null = " false " />
     </ property >
     < property name = " UserPwd "  type = " String " >
       < column name = " UserPwd "  length = " 50 "  sql - type = " nvarchar "  not - null = " false " />
     </ property >
     < property name = " UserAge "  type = " Int32 " >
       < column name = " UserAge "  length = " 4 "  sql - type = " int "   />
     </ property >
   </ class >
</ hibernate - mapping >

 

      基本工作还剩下个配置文件hibernate.cfg.xml

代码

<? xml version = " 1.0 "  encoding = " utf-8 "   ?>
< hibernate - configuration xmlns = " urn:nhibernate-configuration-2.2 " >
   < session - factory >
     < property name = " connection.driver_class " > NHibernate.Driver.SqlClientDriver </ property >
     < property name = " connection.connection_string " > Server = localhost;uid = sa;pwd = 123456 ;database = NunitUser;Integrated Security = SSPI </ property >
     < property name = " dialect " > NHibernate.Dialect.MsSql2000Dialect </ property >
     < property name = " adonet.batch_size " > 100 </ property >
     < property name = ' proxyfactory.factory_class ' >
      NHibernate.ByteCode.Castle.ProxyFactoryFactory,NHibernate.ByteCode.Castle
     </ property >
     < mapping assembly = " NHUser " />
   </ session - factory >
</ hibernate - configuration >

 

      OK！准备工作over了，下面看看CRUD的操作代码吧

代码

namespace  NHUser
{
     public   partial   class  NHCRUD : Form
    {
         public  NHCRUD()
        {
            InitializeComponent();
        }

         private   void  btnOK_Click( object  sender, EventArgs e)
        {
             try
            {
                 string  username  =   this .tbUserName.Text.ToString();
                 string  userpwd  =   this .tbUserPwd.Text.ToString();
                 int  userage  =  Convert.ToInt32( this .tbUserAge.Text.ToString());

                 // 定义配置文件
                Configuration cfg  =   new  Configuration();
                cfg.Configure();

                 // 创建会话工厂
                ISessionFactory factory  =  cfg.BuildSessionFactory();
                ISession session  =  factory.OpenSession();
                 // 用户赋值
                User user  =   new  User();
                user.UserName  =  username;
                user.UserPwd  =  userpwd;
                user.UserAge  =  userage;

                 // 开启事务
                ITransaction trans  =  session.BeginTransaction();
                 try
                {
                    session.Save(user);

                    //Commit
                    trans.Commit();
                    MessageBox.Show( " 用户数据插入成功！ " ,  " 系统提示！ " );
                     this .Close();
                }
                 catch  (Exception ex)
                {
                    trans.Rollback();
                    MessageBox.Show( " 用户数据插入失败！ "   +  ex.Message,  " 系统提示！ " );
                }
            }
             catch  (Exception ex)
            {
                MessageBox.Show(ex.Message,  " 错误提示！ " );
            }
        }

         ///   <summary>
         ///  查询指定数据
         ///   </summary>
         private   void  btnRead_Click( object  sender, EventArgs e)
        {
             // 定义配置文件
            Configuration cfg  =   new  Configuration();
            cfg.Configure();
             // 创建会话工厂
            ISessionFactory factory  =  cfg.BuildSessionFactory();
             using  (ISession session  =  factory.OpenSession())
            {
                IList users  =  session.CreateCriteria( typeof (User)).Add(Expression.Eq( " UserName " ,  " dukeyongwang " )).List();

                 foreach  (User user  in  users)
                {
                    Console.WriteLine( " UserID: "   +  user.UserID  +   " ——>UserName: "   +  user.UserName  +   " ——>UserPwd: "   +  user.UserPwd  +   " ——>UserAge: "   +  user.UserAge);
                }
            }
        }

         ///   <summary>
         ///  修改
         ///   </summary>
         private   void  btnUpdate_Click( object  sender, EventArgs e)
        {
             // 定义配置文件
            Configuration cfg  =   new  Configuration();
            cfg.Configure();
             // 创建会话工厂
            ISessionFactory factory  =  cfg.BuildSessionFactory();

             try
            {
                 using  (ISession session  =  factory.OpenSession())
                {
                    User user  =  session.Load( typeof (User),  5 )  as  User;

                    Console.WriteLine( " 修改前==>>UserID: "   +  user.UserID  +   " ——>UserName: "   +  user.UserName  +   " ——>UserPwd: "   +  user.UserPwd  +   " ——>UserAge: "   +  user.UserAge);

                    user.UserName  =   " dukeyongwang " ;
                    user.UserPwd  =   " dkwang " ;
                    user.UserAge  =   25 ;

                     using  (ITransaction trans  =  session.BeginTransaction())
                    {
                        session.Update(user, user.UserID);

                        User updateUser  =  session.Load( typeof (User), user.UserID)  as  User;

                         // 修改后
                        Console.WriteLine( " 修改后==>>UserID: "   +  updateUser.UserID  +   " ——>UserName: "   +  updateUser.UserName  +   " ——>UserPwd: "   +  updateUser.UserPwd  +   " ——>UserAge: "   +  updateUser.UserAge);

                        trans.Commit();
                    }
                }
            }
             catch  (Exception ex)
            {
                MessageBox.Show( " 修改时错误： "   +  ex.Message,  " 错误提示！ " );
            }
        }


         ///   <summary>
         ///  删除(可通过查询出来的实体对象，然后删除)
         ///   </summary>
         private   void  btnDel_Click( object  sender, EventArgs e)
        {
            // 定义配置文件
            Configuration cfg  =   new  Configuration();
           cfg.Configure();
            // 创建会话工厂
            ISessionFactory factory  =  cfg.BuildSessionFactory();

             using  (ISession session  =  factory.OpenSession())
            {
                 using  (ITransaction trans  =  session.BeginTransaction())
                {
                    User newUser  =  session.Load( typeof (User),  6 )  as  User;
                     // 删除
                    session.Delete(newUser);
                    
                    trans.Commit();
                }
            }
        }
    }
}

 

     运行以上代码，就可以实现数据的CRUD，感觉没有SQL，代码清爽了许多。呵呵。。。。

     ②：Linq

     在linq中少了NHibernate的映射文件，这部分实现在实体类中通过TableAttribute和ColumnAttribute实现，少建一个xml文件，也许你会说，现在的映射文件可以自动生成，好吧，我承认的确是可以。

代码

[Table(Name = " UserInfo " )]
     public   class  User
    {
         private   int  userID;
         ///   <summary>
         ///  用户ID
         ///   </summary>
        [Column(DbType = " int " ,IsPrimaryKey = true ,IsDbGenerated = true )]
         public   int  UserID
        {
             get
            {
                 return  userID;
            }
             set
            {
                userID  =  value;
            }
        }

         private   string  userName;
         ///   <summary>
         ///  用户姓名
         ///   </summary>
        [Column(DbType = " nvarchar(50) " )]
         public   string  UserName
        {
             get
            {
                 return  userName;
            }
             set
            {
                userName  =  value;
            }
        }

         private   string  userPwd;
         ///   <summary>
         ///  用户密码
         ///   </summary>
        [Column(DbType = " nvarchar(50) " )]
         public   string  UserPwd
        {
             get
            {
                 return  userPwd;
            }
             set
            {
                userPwd  =  value;
            }
        }

         private   int  userAge;
         ///   <summary>
         ///  用户年龄
         ///   </summary>
        [Column(DbType = " int " )]
         public   int  UserAge
        {
             get
            {
                 return  userAge;
            }
             set
            {
                userAge  =  value;
            }
        }
    }

 

    好了，现在就可以看看在LINQ中如何完成CRUD的操作：

代码

namespace  LinqUser
{
     public   partial   class  LinqCRUD : Form
    {

        //映射实体

        DataContext objContext  =   null ;

         public  LinqCRUD()
        {
            InitializeComponent();
             string  strConnection  =   " Server=localhost;uid=sa;pwd=123456;database=NunitUser;Integrated Security=SSPI " ;
            objContext  =   new  DataContext(strConnection);
        }

         #region  数据CRUD
         ///   <summary>
         ///  数据插入
         ///   </summary>
         private   void  btnCreate_Click( object  sender, EventArgs e)
        {
             try
            {
                 string  userName  =   this .tbUserName.Text.ToString();
                 string  userPwd  =   this .tbUserPwd.Text.ToString();
                 int  userAge  =  Convert.ToInt32( this .tbUserAge.Text.ToString());

                User user  =   new  User();
                user.UserName  =  userName;
                user.UserPwd  =  userPwd;
                user.UserAge  =  userAge;
                
                 // 插入
                objContext.GetTable < User > ().InsertOnSubmit(user);
                 // 提交
                objContext.SubmitChanges();

                MessageBox.Show( " 插入数据成功！ " ,  " 系统提示！ " );
            }
             catch  (Exception ex)
            {
                MessageBox.Show( " 插入数据时错误： "   +  ex.Message,  " 系统提示！ " );
            }
        }

         ///   <summary>
         ///  数据修改
         ///   </summary>
         private   void  btnUpdate_Click( object  sender, EventArgs e)
        {
             try
            {
                var myUpdate  =  from user  in  objContext.GetTable < User > ()
                                where  user.UserID  ==   1
                               select user;
                User userUpdate  =  myUpdate.First < User > ()  as  User;
                 if  ( null   ==  userUpdate)  return ;
                userUpdate.UserName  =   this .tbUserName.Text.ToString();
                userUpdate.UserPwd  =   this .tbUserPwd.Text.ToString();
                userUpdate.UserAge  =  Convert.ToInt32( this .tbUserAge.Text.ToString());

                 // 提交
                objContext.SubmitChanges();

                MessageBox.Show( " 修改数据成功！ " ,  " 系统提示！ " );
            }
             catch  (Exception ex)
            {
                MessageBox.Show( " 修改数据时错误： "   +  ex.Message,  " 系统提示！ " );
            }
        }

         ///   <summary>
         ///  数据删除
         ///   </summary>
         private   void  btnDel_Click( object  sender, EventArgs e)
        {
             try
            {
                var myDel  =  from user  in  objContext.GetTable < User > ()
                             where  user.UserID  ==   1
                            select user;
                User userDel  =  myDel.First < User > ();
                 if  ( null   ==  userDel)  return ;

                 // 删除
                objContext.GetTable < User > ().DeleteOnSubmit(userDel);

                 // 提交
                objContext.SubmitChanges();

                MessageBox.Show( " 删除数据成功！ " ,  " 系统提示！ " );
            }
             catch  (Exception ex)
            {
                MessageBox.Show( " 删除数据时出错： "   +  ex.Message,  " 系统提示！ " );
            }
        }

         ///   <summary>
         ///  数据查询
         ///   </summary>
         private   void  btnRead_Click( object  sender, EventArgs e)
        {
             try
            {
                var myQuery  =  from user  in  objContext.GetTable < User > ()
                               where  user.UserID  ==   1
                              select user;

                 if  (myQuery.Count < User > ()  <=   0 )  return ;

                 foreach  (User user  in  myQuery)
                {
                    Console.WriteLine( " 用户信息：UserID——> "   +  user.UserID  +   " 、UserName——> "   +  user.UserName  +   " 、UserPwd——> "   +  user.UserPwd  +   " 、UserAge——> "   +  user.UserAge);
                }

                MessageBox.Show( " 查询数据成功！ " ,  " 系统提示！ " );

            }
             catch  (Exception ex)
            {
                MessageBox.Show( " 查询数据时错误： "   +  ex.Message,  " 系统提示！ " );
            }
        }
         #endregion
    }
}

 

      到这里，LINQ的操作也结束了。运行感受一下吧。

      先说说我的感受吧，用NHibernate明显感觉到效率没有原生的SQL语句的好，可能只是插入一条语句，没有批量的处理，Linq反而没感觉到比NHibernate效率低。如果是对数据库操作的实时性要求很高的话，可能不太适合使用ORM技术，当然了，才接触到这些东西，也许有其它的解决办法也说不定，待自己慢慢研究吧！！