Entity Framework菜鸟初飞【4】—— 增删改查

针对已经生成的实体类模型，简要演练下增删改查

using System;using System.Linq;namespace EF{    class Program    {        static void Main(string[] args)        {            using (EF.DFEntities DF = new DFEntities())            {                #region 清空演练                DF.ExecuteStoreCommand("delete from " + DF.UserInfoes.EntitySet.ElementType.Name);                //因为表名与关键字重名，因此加中括号                DF.ExecuteStoreCommand("delete from [" + DF.Users.EntitySet.ElementType.Name + "]");                //表里头是否有数据                bool HasData = DF.Users.Any();                if (!HasData)                {                     Console.WriteLine("1、数据已经清空");                     Console.WriteLine("————————————————");                }                #endregion                #region 添加演练                //创建实体类                User setUser = new User();                //赋值                setUser.UserName = "Joe Cai";                setUser.UserPassword = "123456";                DF.AddToUsers(setUser);//添加父表信息                UserInfo setUserInfo = new UserInfo();                setUserInfo.UserEmail = "[e-mail]";                setUserInfo.UserMobile = "15111111111";                setUserInfo.UserTelephone = "0755-12345678";                setUser.UserInfoes.Add(setUserInfo);//添加子表信息                //表里头是否有数据                bool HasAddUser = DF.Users.Any();                if (!HasAddUser)                {                    Console.WriteLine("2、未添加账号");                    Console.WriteLine("————————————————");                }                DF.SaveChanges();//保存到数据库                //表里头是否有数据                HasAddUser = DF.Users.Any();                if (HasAddUser)                {                    Console.WriteLine("3、已经添加账号");                    Console.WriteLine("————————————————");                }                #endregion                #region 读取演练                UserInfo getUserInfo = DF.UserInfoes.Where(it => it.UserEmail == "[e-mail]").FirstOrDefault();                if (getUserInfo != null)                {                    if (getUserInfo.User == null)                    {                        getUserInfo.UserReference.Load();//加载父表信息                    }                    User getUser = getUserInfo.User;//因为已经加载，故能读取到父表信息                    Console.WriteLine("————————————————");                    Console.WriteLine("我的账号");                    Console.WriteLine(string.Format("      UserId : {0}", getUser.UserId));                    Console.WriteLine(string.Format("    UserName : {0}", getUser.UserName));                    Console.WriteLine(string.Format("UserPassword : {0}", getUser.UserPassword));                    Console.WriteLine("================================");                    Console.WriteLine("我的账号详细信息");                    Console.WriteLine(string.Format("   UserInfoId : {0}", getUserInfo.UserInfoId));                    Console.WriteLine(string.Format("    UserEmail : {0}", getUserInfo.UserEmail));                    Console.WriteLine(string.Format("   UserMobile : {0}", getUserInfo.UserMobile));                    Console.WriteLine(string.Format("UserTelephone : {0}", getUserInfo.UserTelephone));                    Console.WriteLine("————————————————");                }                else                {                    Console.WriteLine("没有相关账号信息");                }                #endregion                Console.ReadLine();            }       }}

运行结果如下：

下面附上一系列关于Entity Framework查询的教程

Entity Framework 学习初级篇2--ObjectContext、ObjectQuery、ObjectStateEntry、ObjectStateManager类的介绍

Entity Framework 学习初级篇3-- LINQ TO Entities

Entity Framework 学习初级篇4--Entity SQL

Entity Framework 学习初级篇5--ObjectQuery查询及方法

Entity Framework 学习初级篇6--EntityClient

Entity Framework 学习初级篇7--基本操作：增加、更新、删除、事务