在 Asp.NET MVC 中按日期求和 Linq

Question

SiteCode    |     date      |softwarename  |  Success  |      Error
ASZ             2017-08-5         a              1             1
ASZ             2017-08-5         b              2             2
ASZ             2017-08-5         a              3             3
ASZ             2017-08-6         a              6             6
NBL             2017-08-5         a              5             5

var CurrentCustomer = Database.Session.Query<Customer>()
    .FirstOrDefault(x => x.deleted_at == null 
        && x.Customer_Username == User.Identity.Name);

if(CurrentCustomer != null) 
{
    var CurrentDepValues = Database.Session.Query<deployments>()
        .Where(x => x.SiteCode == CurrentCustomer.SiteCode 
            && x.softwarename == current_type)
        .OrderBy(x => x.date)
        .ToList();
}

我有一个这样的数据库。我想得到如下输出。相同的日期值应该是总和。

SiteCode    |     date      |softwarename  |  Success  |      Error
ASZ             2017-08-5         a              4             4
ASZ             2017-08-6         a              6             6

Answer 1

使用GroupBy：

if(CurrentCustomer != null) {
     var CurrentDepValues = Database.Session.Query<deployments>()
      .Where(x => x.SiteCode == CurrentCustomer.SiteCode 
          && x.softwarename == current_type)
      .GroupBy (x => new {x.SiteCode, x.date, x.softwarename})
      .Select (g => new {
            SiteCode = g.Key.SiteCode,
            Date = g.Key.date,
            SoftwareName = g.Key.softwarename,
            Success = g.Sum(x => x.Success),
            Error = g.Sum(x => x.Error)
      })
      .OrderBy(x => x.Date)
      .ToList();
}   

编辑

上面将创建一个匿名类型。 如果你想得到List<Models.deployments>，你应该在select lambda中这样做：

.Select (g => new Models.deployments {
            SiteCode = g.Key.SiteCode,
            Date = g.Key.date,
            SoftwareName = g.Key.softwarename,
            Success = g.Sum(x => x.Success),
            Error = g.Sum(x => x.Error)
      })