EF 增删改查
StudentEntities entities = new StudentEntities(); //初始化對象Register register = new Register();#region 增加//register.UserName = "張三";//register.Pwd = "123";//register.Sex = "男";//register.Phone = "123456";//register.Age = "20";//register.Address = "河南鄭州";//entities.Register.Add(register); //添加一個集合使用Add//entities.SaveChanges(); //保存#endregion#region 刪除//Register r = entities.Register.Where(i=>i.Id==39).SingleOrDefault(); //在這里需要注意的是Lambda表達式的i屬性Register,它是一個集合,所以需要它.出來他的id項//entities.Register.Remove(r); //刪除使用的是Remove//entities.SaveChanges();#endregion#region 修改//Register rr = entities.Register.Where(i => i.Id == 40).SingleOrDefault(); //修改時間記得先查詢要修改的條件//rr.UserName = "zhangsan"; //在這里需要注意的是接受的對象//rr.Pwd = "456";//rr.Sex = "女";//rr.Phone = "123456789";//rr.Age = "20";//rr.Address = "北京";//entities.SaveChanges(); //保存#endregion#region 查詢//Register rrr = entities.Register.Where(i => i.Id == 41).SingleOrDefault();//Console.WriteLine("{0},{1},{2}",rrr.Id,rrr.UserName,rrr.Pwd);//Register rrr = entities.Register.SelectMany(i=>i.Id==40&&i.Id==41).SelectMany();
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轉載于:https://www.cnblogs.com/laopo/p/5133475.html
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