[英]How can I use Distinct operator in C# LINQ query
我想使用c#中的以下代码选择唯一的EventYear,它给出重复的值。 我的表(EventMasters)
结构是(EventYear (string), EventCode, EventDescription)
我想选择唯一或不同的EventYear
public ActionResult EventYearsMenu()
{
var eventyears = storeDB.EventMasters.Distinct().ToList().OrderByDescending(c => c.EventYear== c.EventYear.Distinct());
return PartialView(eventyears);
}
我想选择唯一或不同的
EventYear
不只是:
var eventyears = storeDB.EventMasters
.Select(c => c.EventYear)
.Distinct()
.ToList();
这样尝试
var eventyears = from Data in storeDB.EventMasters
where (this == that) // Write your Logic
select Data;
if (eventyears != null)
{
/// do your code,,.,,,
}
尝试跟随
var eventyears = storeDB.EventMasters
.GroupBy(c=>c.EventYear)
.Select(items=>items.First())
.SelectMany(item->item)
.ToList()
.OrderByDescending(c => c.EventYear == c.EventYear.Distinct());
它将采用不同的项目(基于EventYear)。 (即使EventYear相同的项目在某些其他属性上具有不同的值,也可能将其归类为相同的项目)
尝试这个
var eventyears = storeDB.EventMasters.ToList()
.OrderByDescending(c => c.EventYear == c.EventYear).Distinct();
您可以尝试此代码。
var eventyears = storeDB.EventMasters.Distinct(q => q.EventYear.).ToList().OrderByDescending(c => c.EventYear);
return PartialView(eventyears);
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.