Linq查询DateTime.Date.DayOfWeek [英] Linq query DateTime.Date.DayOfWeek

问题描述

尝试仅在1年的周四获得

Trying to get only Thursdays of 1 year back

using (var context = new Context1())
{
      // Get 1 year back only Thursday
      var oneYearEarlier = DateTime.Now.AddYears(-1);

      var query = (from c in context.Daily25Data
                   where c.Date > oneYearEarlier && c.Date.DayOfWeek == DayOfWeek.Thursday
                   select c).ToList();

      Console.WriteLine(query);
}

并获得

附加信息：LINQ to Entities中支持的指定类型成员DayOfWeek不是
。只支持初始化器，实体成员和
实体导航属性。

Additional information: The specified type member 'DayOfWeek' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported.

推荐答案

这是使用EntityFunctions.DiffDays

This is a clever solution using EntityFunctions.DiffDays

的聪明解决方案：

DateTime firstSunday = new DateTime(1753, 1, 7); 
var bookings = from b in this.db.Bookings 
               where EntityFunctions.DiffDays(firstSunday, b.StartDateTime) % 7 == 1 
               select b;

这篇关于Linq查询DateTime.Date.DayOfWeek的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！