C# Linq:group by不';行不通
我无法让我的团队正常工作。有人知道为什么吗C# Linq:group by不';行不通,c#,linq,C#,Linq,我无法让我的团队正常工作。有人知道为什么吗 public void MonthlyTurnover(int year, int month) { var q1 = (from sp in _db.Species from p in _db.Pets from b in _db.Bookings.Where(x => x.ExpectedArrivalTime.Year == year &&
public void MonthlyTurnover(int year, int month) {
var q1 = (from sp in _db.Species
from p in _db.Pets
from b in _db.Bookings.Where(x => x.ExpectedArrivalTime.Year == year &&
x.ExpectedArrivalTime.Month == month)
where p.SpeciesId == sp.Id && b.PetId == p.Id && b.PetId == p.Id
select new {sp.SpeicesName, Sum = b.Services.Sum(i => i.Price)}).ToList();
foreach (var v in q1) {
Console.WriteLine(v);
}
}
没有分组我能得到什么
public void MonthlyTurnover(int year, int month) {
var q1 = (from sp in _db.Species
from p in _db.Pets
from b in _db.Bookings.Where(x => x.ExpectedArrivalTime.Year == year &&
x.ExpectedArrivalTime.Month == month)
where p.SpeciesId == sp.Id && b.PetId == p.Id && b.PetId == p.Id
select new {sp.SpeicesName, Sum = b.Services.Sum(i => i.Price)})
.GroupBy(x => new{x.SpeicesName, x.Sum}).ToList();
foreach (var v in q1) {
Console.WriteLine(v.Key);
}
}
我从小组中得到了什么
我想要的是
不要按总和分组。。。只需按物种名称分组
...
.GroupBy(x => x.SpeicesName).ToList();
现在你有了一系列的组,其中关键是物种名称。您可以显示物种名称(一次),然后将所有单个总和相加
foreach (var v in q1)
{
Console.WriteLine("{0}: {1}", v.Key, v.Sum(x => x.Sum)); // "Dog: 7500", "Cat: 3500", etc
}
仅按
SpeicesName
分组,请尝试以下操作:
var q1 = (from sp in _db.Species
from p in _db.Pets
from b in _db.Bookings.Where(x => x.ExpectedArrivalTime.Year == year &&
x.ExpectedArrivalTime.Month == month)
where p.SpeciesId == sp.Id && b.PetId == p.Id && b.PetId == p.Id
select new {sp.SpeicesName, Sum = b.Services.Sum(i => i.Price)})
.GroupBy(x => x.SpeicesName).Select(g=>new {SpeicesName=g.Key,Sum=g.Sum(e=>e.Sum)}).ToList();
谢谢,那正是我需要的:)谢谢,那正是我需要的:)