C#实体模型增删改查

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namespace ConsoleApplication7{    class Program    {        static void Main(string[] args)        {            //user hp = new user();            //hp.name = "郝鹏";            //hp.age = 25;            //hp.degree = "硕士";            //hp.profession = "学生";            //hp.address = "金华南路";            //hp.remark = "无";            //           //user hpeng = new user()           //{           // name = "郝鹏";           // age = 25;           // degree = "硕士";           // profession = "学生";           // address = "金华南路";           // remark = "无";           // }            //增加            using (mydbEntities db = new mydbEntities())            {                user hp = new user();                hp.name = "郝鹏";                hp.age = 25;                hp.degree = "硕士";                hp.profession = "学生";                hp.address = "金华南路";                hp.remark = "无";                //第一种                db.user.Add(hp);                db.SaveChanges();                //第二种                db.Entry(hp).State = EntityState.Added;                db.SaveChanges();            }            //删除            using (mydbEntities db = new mydbEntities())            {                user hp = new user();                hp.name = "郝鹏";                hp.age = 25;                hp.degree = "硕士";                hp.profession = "学生";                hp.address = "金华南路";                hp.remark = "无";                //第一种                //实体添加到上下文中                db.user.Attach(hp);                db.user.Remove(hp);                db.SaveChanges();                //第二种                db.Entry(hp).State = EntityState.Deleted;                db.SaveChanges();            }            //条件删除            using (mydbEntities db = new mydbEntities())            {                user hp = db.user.First(p => p.name == "郝鹏");                //第一种                db.user.Remove(hp);                db.SaveChanges();                //第二种                db.Entry(hp).State = EntityState.Deleted;                db.SaveChanges();            }            //修改            using (mydbEntities db = new mydbEntities())            {                user hp = new user();                hp.name = "郝鹏";                hp.age = 25;                hp.degree = "硕士";                hp.profession = "学生";                hp.address = "金华南路";                hp.remark = "无";                db.user.Attach(hp);                db.Entry(hp).State = EntityState.Modified;                db.SaveChanges();                user hp1 = db.user.First(p => p.name == "郝鹏");                hp1.remark = "在读硕士";                db.SaveChanges();            }            //查询所有            using (mydbEntities db = new mydbEntities())            {                IQueryable result = db.user.Select(p=>p);                //条件查询                //IQueryable result = db.user.Select(p=>p.name=="XXX");                // IQueryable result = db.user.Wheres(p=>p.name=="XXX");                foreach (user item in result)                {                    Console.WriteLine(item.name);                }                //执行sql语句               // db.user.SqlQuery(string,object[]);                foreach(var item in db.user)                {                                    }            }        }    }}
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