添加
//声明一个上下文 bookshopEntities dbContext = new bookshopEntities(); users user = new users(); user.loginid = "qweras123dfqwe"; user.loginpwd = "qwer2asdfqwe"; user.name = "qwerasdf123qwe"; user.address = "qwerasdfqwe"; user.phone = "qwerasdfqwe2"; user.mail = "sss12231"; user.userstateid = 1; user.userroleid = 1; ////告诉ef对实体执行插入操作 dbcontext.users.add(user); dbContext.SaveChanges();
修改(更新)
1.修改该对象的所有属性
bookshopEntities dbContext = new bookshopEntities(); Users user = new Users(); user.LoginId = "zhanssss"; user.LoginPwd = "zhansssss"; user.Name = "zhanssss"; user.Address = "zhanssss"; user.Phone = "zhanssss"; user.Mail = "zhanssss"; user.UserStateId = 1;
dbContext.SaveChanges();
user.UserRoleId = 1; user.Id = 110; dbContext.Entry<Users>(user).State = System.Data.EntityState.Modified;
2.修改该对象的一个或多个属性
Users user = new Users(); user.LoginPwd = "412213"; user.Id = 110;//修改任何属性都必须指定唯一主键 dbContext.Entry<Users>(user).Property("LoginPwd").IsModified = true;
//dbContext.Entry<Users>(user).Property(c => new { c.LoginPwd,c.Money}); lambda表达式简写
dbContext.SaveChanges();
批量更新
删除需()指定唯一主键)
db.Entry<Question>(question).State=EntityState.Deleted;
或
db.Question.Remove(question);
若需批量删除,只能一条一条删,ef已删掉批量删除的方法
foreach (var item in temp.ToList()) { db.Dtb.Remove(item); }