自己动手写ORM框架

提起ORM框架,大家都很熟悉，网上流行的ORM框架有很多，其中出名的有一些，不出名的更是数不胜数。

下面是自己实现的一个简单的ORM框架,实现了常用的增删查改功能,供大家研究ORM实现原理。

功能描述：

1.支持Update语句

2.支持Insert语句

3. 支持Delete语句

4.支持事务

5.支持自定义增删查改语句

6.支持单表查询 ，多表查询

7.支持排序，分页语句

8.结果集可以是DataTable  也可 以是 List<T> 泛型集合，还可以是实体对象

9.结果集支持foreach 遍历

10.支持Oracle和MSSQLServer数据库

大部分常用功能下面代码已做了演示

DbMapper.1.0.0.3.下载地址

示例：

 using System;
 using System.Collections.Generic;
 using System.Text;
 using DBMapper;
 using System.Data;

 namespace DbMapperTest
 {
     class Program
     {
         static void Main(string[] args)
         {
             try
             {
                 string str_ticks=System.DateTime.Now.Ticks.ToString();
                 int jlbh = int.Parse(str_ticks.Substring(str_ticks.Length - , ));
                 //---oracle测试
                 using (var dbMap = DbMapper.CreateDbMapper(DbMapper.PROVIDER_ORACLE,
                      "Password=test;User ID=test;Data Source=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)"
                      + "(HOST=localhost)(PORT=1521)))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=testdb)));"))

                 //----sqlserver测试
                 //using(var dbMap=DbMapper.CreateDbMapper(DbMapper.PROVIDER_SQLSERVER,"Data Source=DINT-PC;Integrated Security=True; database=TEST"))
                 {
                     //插入记录
                     dbMap.Insert<Person>(new Person
                     {
                         JLBH = jlbh,
                         NAME = "索额图",
                         ADDRESS = "皇宫",
                         AGE = ,
                         PNO = "zzzzzzzzzzzzzzzzz"
                     });

                     dbMap.Insert<Course>(new Course()
                     {
                         JLBH = jlbh,
                         NAME = "计算机科学与技术",
                         TIME = DateTime.Now.ToString()
                     });
                     dbMap.Insert<PersonCourse>(new PersonCourse()
                     {
                         COUR_ID = jlbh,
                         PERSON_ID = jlbh,
                     });
                     dbMap.Execute(false);
                     if(dbMap.Query<Person>("select * from Person where JLBH=:JLBH",new Person{JLBH=jlbh}).Count>)
                     Console.WriteLine("插入Person记录{0}成功", jlbh);

                     if (dbMap.Query<Course>("select * from Course where JLBH=:JLBH", new Course { JLBH = jlbh }).Count > )
                     Console.WriteLine("插入Course记录{0}成功", jlbh);

                     if (dbMap.Query<PersonCourse>("select * from PERSON_COURSE where PERSON_ID=:PERSON_ID", new PersonCourse { PERSON_ID = jlbh }).Count > )
                     Console.WriteLine("插入PersonCourse记录{0}成功", jlbh);

                     /*----------------修改--------------------------*/
                     Console.WriteLine("");
                     Console.WriteLine("-----------------修改-----------------");
                     dbMap.Update<Course>(new Course {
                        JLBH=jlbh,
                        NAME = "计算机科学与技术（修正版）"
                     });
                     int aff=dbMap.Execute();
                     if (aff > ) {
                         Console.WriteLine("插入Course记录{0}成功", jlbh);
                     }

                     /*----------------单记录查询---------------*/
                     Console.WriteLine("");
                     Console.WriteLine("----------------单记录查询---------------");
                     //动态对象传递参数 .NET4.0及以上版本才支持的
                     Person aPerson = dbMap.Query<Person>("select * from Person where JLBH=:JLBH",
                     new {
                         JLBH=jlbh
                     }).First;
                     Console.WriteLine("{0} {1} {2} {3}", aPerson.JLBH, aPerson.NAME, aPerson.PNO, aPerson.ADDRESS);

                     /*------------------------foreach遍历结果集--------------------------------*/
                     Console.WriteLine("");
                     Console.WriteLine("--------foreach遍历结果集-------------");
                     foreach (Person cc in dbMap.Query<Person, Course, PersonCourse>(@"select P.JLBH PERSON#JLBH,P.NAME PERSON#NAME,P.PNO,P.ADDRESS,P.AGE,
                        C.NAME COURSE#NAME,C.TIME from PERSON P,COURSE C,PERSON_COURSE PC
                        where P.JLBH=PC.PERSON_ID and C.JLBH=PC.COUR_ID", null, null, null).OrderBy("PERSON#JLBH", true).Take())
                     {
                         Console.WriteLine("{0} {1} {2}", cc.JLBH, cc.NAME, cc.PNO);
                     }

                     /*------------------------------返回结果数量 Count属性-------------------------------------*/
                     Console.WriteLine(""); Console.WriteLine("");
                     Console.WriteLine("-------------------返回结果数量 Count属性-----------------");
                     int countPersons = dbMap.Query<Person>("select * from Person", null).Count;
                     Console.WriteLine(countPersons.ToString());

                     /*---------------------------多表查询----------------------------------------*/
                     Console.WriteLine(""); Console.WriteLine("");
                     Console.WriteLine("--------------------多表查询----------------------");

                     DataTable at = dbMap.Query<Object>(@"select P.JLBH PERSON#JLBH,P.NAME PERSON#NAME,P.PNO,P.ADDRESS,P.AGE,
                        C.NAME COURSE#NAME,C.TIME from PERSON P,COURSE C,PERSON_COURSE PC
                        where P.JLBH=PC.PERSON_ID and C.JLBH=PC.COUR_ID", null).OrderBy("PERSON#JLBH", false).Skip().Take().ToTable();
                     foreach (DataRow arow in at.Rows)
                     {
                         Console.WriteLine("{0} {1} {2} {3} {4}", arow["PERSON#JLBH"], arow["PERSON#NAME"], arow["COURSE#NAME"], arow["TIME"], arow["PNO"]);
                     }

                     /*-------------------------返回结果集-----------------------------*/
                     Console.WriteLine(""); Console.WriteLine("");
                     Console.WriteLine("--------------------返回结果集----------------------");
                     List<Person> lstPersons = dbMap.Query<Person>("select * from Person", null).OrderBy("JLBH", true).Skip().Take().ToList();
                     foreach (Person p in lstPersons)
                     {
                         Console.WriteLine("{0} {1} {2} {3} {4}", p.JLBH, p.NAME, p.PNO, p.AGE, p.ADDRESS);
                     }
                 }
             }
             catch(Exception ex){
                 Console.WriteLine(ex.Message);
             }
         }
     }

     /*还差一个根据表自动生成对象的工具  这里手动生成*/
     class Person : IDbTableNaming {
         [PrimaryKey]//标示该列为主键  Update 函数需要
         public int JLBH { get; set; }
         public string NAME { get; set; }
         public string PNO { get; set; }
         public string ADDRESS { get; set; }
         public int AGE { get; set; }
         string IDbTableNaming.DBTableName//映射到数据库中的表名  如果没有 则默认为类名
         {
             get { return "PERSON"; }
         }
     }
     class Course : IDbTableNaming {
         [PrimaryKey]
         public int JLBH { get; set; }
         public string NAME { get; set; }
         public string TIME { get; set; }
         string IDbTableNaming.DBTableName
         {
             get { return "COURSE"; }
         }
     }
     class PersonCourse:IDbTableNaming {
         public int PERSON_ID { get; set; }
         public int COUR_ID { get; set; }
         string IDbTableNaming.DBTableName
         {
             get { return "PERSON_COURSE"; }
         }
     }
 }