MVC+EF 的增删改查操做

一、 //建立EF映射对象数据集
static Models.db_JiaoYouEntities DbDeleteData = new Models.db_JiaoYouEntities();

二、 #region 获得数据集合+Query()
/// <summary>
/// 获得数据集合
/// </summary>
/// <returns></returns>
public List<Models.tb_Msg> Query()
{
Models.db_JiaoYouEntities DbQueryData = new Models.db_JiaoYouEntities();
List<Models.tb_Msg> MsgList = DbQueryData.tb_Msg.Where(c => c.Sender == "b").ToList();

return MsgList;
}
#endregion

三、 #region Mvc +EF 的 add()增长操做
// 一、声明EF
// 二、完成对应数据表对象的数据添加
// 三、调用声明的ef的对应表的添加操做
// 四、ef的SaveChange()操做
public static string add() {

Models.db_JiaoYouEntities DbData = new Models.db_JiaoYouEntities();
Models.tb_Msg Msg = new Models.tb_Msg();
Msg.ID = 123;
Msg.Accepter = "a";
Msg.CheckRead = true;
Msg.Msg = "info";
Msg.MsgDate = DateTime.Now;
Msg.Sender = "b";
DbData.tb_Msg.Add(Msg);
DbData.SaveChanges();
return "测试成功！";
}
#endregion

四、 #region EF编辑操做
/// <summary>
/// EF编辑操做
/// </summary>
/// <returns></returns>
public static string Edit()
{

Models.db_JiaoYouEntities DbUpdateData = new Models.db_JiaoYouEntities();
Models.tb_Msg UpdateMsg = DbUpdateData.tb_Msg.Where(c => c.Sender == "b" && c.Accepter == "a").FirstOrDefault();
UpdateMsg.Accepter = "c";
DbUpdateData.SaveChanges();

return "ce";

}
#endregion

五、 #region EF删除操做
public static string Delete()
{

//删除要使用主键作标识

Models.tb_Msg MsgRemove = new Models.tb_Msg() { ID = 32 };

DbDeleteData.tb_Msg.Attach(MsgRemove);
DbDeleteData.tb_Msg.Remove(MsgRemove);
DbDeleteData.SaveChanges();
return "";

}
#endregion

六、 #region EF查询操做
/// <summary>
/// EF查询操做
/// </summary>
/// <returns></returns>
public ActionResult Index()
{

// Edit();
// Delete();
// ViewBag.Result = add();

//调用查询方法,将数据采用ViewBag接收数据传递给视图
//ViewBag.List = Query();

return View(); } #endregion