static void Main(string[] args)
{
string connectionString =
@"Data Source=(localdb)\ProjectsV13;Initial Catalog=17bang;Integrated Security=True;";
DbContextOptionsBuilder <BLL.repoistory.SQLDbContext> optionsBuilder = new DbContextOptionsBuilder <BLL.repoistory.SQLDbContext>();
optionsBuilder
.UseLoggerFactory(MyLoggerFactory)
.UseSqlServer(connectionString);
DatabaseFacade db = new SQLDbContext().Database;
db.EnsureDeleted(); //如果存在数据库，就删除之//db.EnsureCreated(); 和Migration有可能冲突，不要混合使用
db.Migrate();
RegisterFactory.Create();
}