使用Entity Framework的前5个具有组的LINQ查询 [英] Top 5 LINQ query with group by using Entity Framework

问题描述

我需要使用实体框架对前5个LINQ查询进行分组，而下面是sql查询，就像我需要LINQ查询一样.

I need top 5 LINQ query with group by using entity framework and below is sql query like that i need LINQ query.

select top 5 
    EventId,
    Datename(day, EventDate) as Day, 
    convert(varchar(3), EventDate, 100) as Month,  
    Datename(yy, EventDate) as year,
    Title, Description, ThumbImage  
from 
    EventGalleries 
group by 
    EventId, Title, EventDate, Description, ThumbImage 
order by 
    EventDate desc

这是我在SQL Server中的表结构:

This is my table structure in SQL Server:

这是我的操作方法，我需要一个linq查询才能将列表返回到我的视图:

This is my action method and I need a linq query to return list to my view:

public ActionResult Gellery()
{
        var list = db.EventGallerys.ToList();// i need linq query here in place of this list
        return View(list);
}

这是我的模型课:

public class EventGallery
{
    [Key]
    public int Sno {get;set;}
    public string ImageName { get; set; }
    public string ThumbImage { get; set; }
    public string Title { get; set; }
    public string Description { get; set; }
    public DateTime EventDate { get; set; }    
    public string EventId { get; set; }
    public string GalleryType { get; set; }  
    public string IP { get; set; }
    public string SubmittedBy { get; set; }
    public DateTime GalleryCreatedDate { get; set; }
    public string Status { get; set; }
   //  Sno,ImageName,ThumbImage,Title,Description,EventDate,GalleryCreatedDate,EventId,GalleryType,Status

    public EventGallery()
    {
        GalleryCreatedDate = DateTime.Now;
        Status = "Active";
    }
}

预先感谢您的努力.

推荐答案

db.EventGallerys
  .GroupBy(eg => new { eg.EventId, eg.Title, eg.EventDate, eg.Description, eg.ThumbImage })
  .OrderByDescending(eg => eg.Key.EventDate)
  .Take(5)
  .AsEnumerable()
  .Select(eg => new {
      EventId = eg.Key.EventId,
      Day = eg.Key.EventDate.ToString("D"), 
      Month = eg.Key.EventDate.ToString("MMM"),  
      Year = eg.Key.EventDate.ToString("yyyy"),
      Title = eg.Key.Title, 
      Description = eg.Key.Description,
      ThumbImage = eg.Key.ThumbImage 
   })
  .ToList();

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