Using GroupBy, Count and Sum in LINQ Lambda Expressions

I have a collection of boxes with the properties weight, volume and owner.

I want to use LINQ to get a summarized list (by owner) of the box information

e.g.

**Owner, Boxes, Total Weight, Total Volume**
Jim,     5,     1430.00,      3.65
George,  2,     37.50,        1.22

Can someone show me how to do this with Lambda expressions?

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小开

        var q = from b in listOfBoxes
group b by b.Owner into g
select new
{
Owner = g.Key,
Boxes = g.Count(),
TotalWeight = g.Sum(item => item.Weight),
TotalVolume = g.Sum(item => item.Volume)
};

小开

var boxSummary = from b in boxes
group b by b.Owner into g
let nrBoxes = g.Count()
let totalWeight = g.Sum(w => w.Weight)
let totalVolume = g.Sum(v => v.Volume)
select new { Owner = g.Key, Boxes = nrBoxes,
TotalWeight = totalWeight,
TotalVolume = totalVolume }

小开

最佳答案

    var ListByOwner = list.GroupBy(l => l.Owner)
.Select(lg =>
new {
Owner = lg.Key,
Boxes = lg.Count(),
TotalWeight = lg.Sum(w => w.Weight),
TotalVolume = lg.Sum(w => w.Volume)
});