使用NHibernate QueryOver，如何在日期之间添加类型安全限制

Question

考虑以下QueryOver（四分之一和中心是传入的变量）：

QueryOver.Of<Activity>()
        .Where(Restrictions.On<Activity>(a => a.StartDate).IsBetween(quarter.StartDate).And(quarter.EndDate) ||
               Restrictions.On<Activity>(a => a.EndDate).IsBetween(quarter.StartDate).And(quarter.EndDate) ||
               Restrictions.And(Restrictions.Lt("StartDate", quarter.StartDate), Restrictions.Gt("EndDate", quarter.EndDate)))  //TODO: Refactor this to remove magic strings
        .And(a => a.Centre == centre)
        .OrderBy(a => a.Title).Asc;

此查询完美无缺，但我想更改以下限制以删除魔术字符串：

Restrictions.And(Restrictions.Lt("StartDate", quarter.StartDate), Restrictions.Gt("EndDate", quarter.EndDate))

以下是实体（为简洁而剪裁）：

public class Quarter
{
    public DateTime StartDate { get; set; }
    public DateTime EndDate { get; set; }

}

public class Activity
{
    public string Title { get; set; }
    public Centre Centre { get; set; }
    public DateTime StartDate { get; set; }
    public DateTime EndDate { get; set; }

}

public class Centre
{
    public string Name { get; set; }
}

那么使用新的QueryOver扩展的类型安全方式是什么，这使我能够删除这些魔术字符串？

Answer 1

这就是你想要的：

Restrictions.And(
    Restrictions.Lt(Projections.Property<Activity>(x => x.StartDate),
                    quarter.StartDate),
    Restrictions.Gt(Projections.Property<Activity>(x => x.EndDate),
                    quarter.EndDate)))

旁注：属性名称不是魔术字符串。