多个LINQ排序依据不工作

Question

我有多个OrderBy但只有第一顺序列正在

public static List<vwData> GetAllData(string startDate, string endDate) 
{ 
    DateTime dtStart = Convert.ToDateTime(startDate).Date; 
    DateTime dtEndDate = Convert.ToDateTime(endDate).Date; 


    var entities = new DataEntities(); 
    var query = from c in entities.vwData 
       let eventDate = EntityFunctions.TruncateTime(c.EventCreateDate) 
       orderby c.EventCreateDate ascending, c.StartDateTime ascending 
       where eventDate >= dtStart && eventDate <= dtEndDate 
       select c; 
    return query.ToList(); 
} 

Answer 1

排序依据应该是条件检查和默认排序是升序

var query = from c in entities.vwData 
      let eventDate = EntityFunctions.TruncateTime(c.EventCreateDate) 
      where eventDate >= dtStart && eventDate <= dtEndDate 
      orderby c.EventCreateDate, c.StartDateTime 
      select c; 
return query.ToList(); 

OR

后使用Linq，我们可以做如下

var query = entities.vwData.Where(i => 
{ 
    var eventDate = EntityFunctions.TruncateTime(i.EventCreateDate); 
    if (eventDate >= dtStart && eventDate <= dtEndDate) 
     return true; 

    return false; 
}) 
.OrderBy(j => j.EventCreateDate) 
.ThenBy(k => k.StartDateTime) 
.Select(m => m); 

return query.ToList(); 

Answer 2

考虑使用ThenBy：

public static List<vwData> GetAllData(string startDate, string endDate) 
{ 
    DateTime dtStart = Convert.ToDateTime(startDate).Date; 
    DateTime dtEndDate = Convert.ToDateTime(endDate).Date; 


    var entities = new DataEntities(); 
    var query = from c in entities.vwData 
      let eventDate = EntityFunctions.TruncateTime(c.EventCreateDate) 
      orderby c.EventCreateDate ascending 
      thenby c.StartDateTime ascending 
      where eventDate >= dtStart && eventDate <= dtEndDate 
      select c; 
    return query.ToList(); 
} 

Answer 3

尝试下面的查询。它会帮助你：

var query = entities.vwData.Where(i => EntityFunctions.TruncateTime(i.OrderDate) >= dtStart && EntityFunctions.TruncateTime(i.OrderDate) <= dtEndDate) 
     .OrderBy(j => j.EventCreateDate) 
     .ThenBy(k => k.StartDateTime) 
     .Select(m => m); 

    return query.ToList();