public static void Main(string[] args)
{
//CreateHostBuilder(args).Build().Run();
//利用Linq to EntityFramework，实现方法：
//GetBy(IList < ProblemStatus > exclude, bool hasSummary, bool descByPublishTime)，
//该方法可以根据输入参数：
//1.IList<ProblemStatus> exclude：不显示（排除）某些状态的求助
//2.bool hasSummary：只显示已有总结的求助（如果传入值为true的话）
//3.bool descByPublishTime：按发布时间正序还是倒序
//实现方法：GetMessage()，靠将消息列表：
//1.所有未读在已读前面
//2.未读和已读各自按生成时间排序
MessageRepository message = new MessageRepository();
IList <Message> messages = message.GetMessage();
ProblemRepository problem = new ProblemRepository();
IList <Problem> problems = problem.GetBy(new List <ProblemStatus> {
ProblemStatus.canceled
}, true, true);
//SqlDbContext context = new SqlDbContext();
//var db = context.Database; //DataBase从何来
////Create数据库的同时建立表结构，
//db.EnsureCreated();
////Enusure：存在才删除，不存在才创建
//db.EnsureDeleted();
//db.Migrate();
//类似于Update-Database: apply all pending migrations
//本身不生成Migrations
//利用EF，插入3个User对象
//SqlDbContext context = new SqlDbContext();
//User user1= new User
//{
// Name = "叶飞",
// Password = 1234,
// IsMale = true,
// BCredit = 12,
// CreateTime = new DateTime(2021, 7, 27)
//};
//User user2 = new User
//{
// Name = "韩佳宝",
// Password = 2345,
// IsMale = true,
// BCredit = 20,
// CreateTime = new DateTime(2021, 7, 1)
//};
//User user3 = new User
//{
// Name = "夏康平",
// Password = 3456,
// IsMale = true,
// BCredit = 25,
// CreateTime = new DateTime(2021, 8, 1)
//};
//context.Add(user1);
//context.Add(user2);
//context.Add(user3);
//通过主键找到其中一个User对象
//User user = context.Find<User>(2);
//修改该User对象的Name属性，将其同步到数据库
//user.Name = "李腾";
//不加载User对象，仅凭其Id用一句Update SQL语句完成上题
//User user = new User { Id = 1 };
//context.Attach<User>(user);
//user.Name = "马云";
//User user = new User { Id = 1 };
//user.Name = "马花藤";
//user.CreateTime = new DateTime(2021, 7, 27);
//context.Update<User>(user);
//删除该用户
//User user = context.Find<User>(3);
//context.Remove<User>(user);
//context.SaveChanges();
}
