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  • 在EF中直接运行SQL命令

    一、在 EF第一个版本(.NET 3.5 SP1)中

    通过将ObjectContext.Connection转换为EntityConnection,

    再把 EntityConnection.StoreConnection转换为SqlConnection。

    有了这个SqlConnection,我们再创建 SqlCommand便能顺利运行SQL命令了。

    例如:

          EntityConnection entityConnection = (EntityConnection)ctx.Connection;
          DbConnection storeConnection = entityConnection.StoreConnection;
          DbCommand cmd = storeConnection.CreateCommand();
          cmd.CommandType = System.Data.CommandType.StoredProcedure;
          cmd.CommandText = "[PRO_USER_DIGITALCARD_CHECK]";

          ....

    二、在EF4(.NET 4)中

    ObjectContext.ExecuteStoreCommand(...)     执行某一并无返回集的SQL 命令,例如ADD,UPDATE,DELETE操作

    ObjectContext.ExecuteStoreQuery<T>(...)     执行某一个查询,并可以将返回集转换为某一对象

    using (var ctx = new MyObjectContext())
    {
        int result = ctx.ExecuteStoreCommand("UPDATE Person SET Name = 'Michael' WHERE PersonID = 1");
    }
    using (var ctx = new MyObjectContext())
    {
        IEnumerable<PersonView> peopleViews = ctx.ExecuteStoreQuery<PersonView>("SELECT PersonID, Name FROM Person");
    }
    
    public class PersonView
    {
        public int PersonID { get; set; }
        public string Name { get; set; }
    }

    三、在EF4.1中

    DbContext将ObjectContext做了包装,

    DbContext.Database就是对应于数据库端信息的封装

    执行SQL命令也从Database类型开始

    using (var ctx = new MyDbContext())
    {
        int result = ctx.Database.ExecuteSqlCommand("UPDATE Person SET Name = 'Michael' WHERE PersonID = 1");
    }
    using (var ctx = new MyDbContext())
    {
        IEnumerable<PersonView> peopleViews = ctx.SqlQuery<PersonView>("SELECT PersonID, Name FROM Person").ToList();
    }
    
    public class PersonView
    {
        public int PersonID { get; set; }
        public string Name { get; set; }
    }

     示例:

    1.无参数查询:
    
    List<UserInfo> list = db.Database.SqlQuery<UserInfo>("select* from UserInfo ").ToList();
    
    2、有参查询
    
    List<UserInfo> list = db.Database.SqlQuery<UserInfo>("select* from UserInfoes where id=@ID ",new SqlParameter("@ID",id)).ToList();
    
    3.EF 执行存储过程或delete 删除语句
    SqlParameter[] paras = new SqlParameter[] {
      new SqlParameter("@ID",id)
    };
    int result = db.Database.ExecuteSqlCommand("delete UserInfoes  where id=@ID", paras);
    int result = db.Database.ExecuteSqlCommand("sp_Userinfos_deleteByID @ID", paras);

    参考文章:

    http://www.cnblogs.com/chengxiaohui/articles/2092001.html

    http://www.360doc.com/content/14/0709/00/5054188_393081769.shtml

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  • 原文地址:https://www.cnblogs.com/msbbc/p/4130768.html
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