Question

我正在制作报告，以便在C＃中使用LINQ显示客户。我想表明不。每种类型的客户。

有3种类型的客户注册，客人和经理。我希望按客户的注册日期和客户类型进行分组。即如果今天有3位客人，4位注册人员和2名经理人员。明天4,5和6是注册的。然后报告应显示当天注册的客户数量。每种类型的单独行。

DATE        TYPEOF CUSTOMER    COUNT
31-10-2013  GUEST              3
31-10-2013  REGISTERED         4
31-10-2013  MANAGER            2
30-10-2013  GUEST              5
30-10-2013  REGISTERED         10
30-10-2013  MANAGER            3

就像这样。

var subquery = from eat in _customerRepo.Table
                           group eat by new { yy = eat.CreatedOnUTC.Value.Year, mm = eat.CreatedOnUTC.Value.Month, dd = eat.CreatedOnUTC.Value.Day } into g
                           select new { Id = g.Min(x => x.Id) };




var query = from c in _customerRepo.Table
                        join cin in subquery.Distinct() on c.Id equals cin.Id
                        select c;

通过上述查询，我获得了当天注册的最小人群提前致谢

Answer 1

var query = _customerRepo.Table
     .GroupBy(c => new {Date = c.Date.Date,  Type = c.TypeOfCustomer})
     .Select(g => new 
                   {
                       Date = g.Key.Date,
                       Type = g.Key.Type, 
                       Count = g.Count
                   }
            )
     .OrderByDescending (r = r.Date);

Answer 2

var query = from c in _customerRepo.Table
            group c by new { c.TypeOfCustomer, c.Date } into g
            orderby g.Key.Date descending,
                    g.Key.TypeOfCustomer == "GUEST" ? 1 :
                    g.Key.TypeOfCustomer == "REGISTERED" ? 2 : 3
            select new {
               g.Key.Date,
               g.Key.TypeOfCustomer,
               Count = g.Count()
            };

如果每日结果不需要第二次订购，则可以删除第二次订购＆gt;注册＆gt;管理器：

var query = from c in _customerRepo.Table
            group c by new { c.TypeOfCustomer, c.Date } into g
            orderby g.Key.Date descending
            select new {
               g.Key.Date,
               g.Key.TypeOfCustomer,
               Count = g.Count()
            };

Linq按日期获取客户组，然后按类型获取

2 个答案: