在以下代码中,查找DataTable dt中的Rate列的总和:
dt.Compute("Sum(Convert(Rate, 'System.Int32'))");
在这种情况下,可以指定group by子句,如SQL Inn order to get Sum基于同一dt Fo的另一列中的值,例如:
----------------------------
Rate | Group |type
----------------------------
100 | A | 1
120 | B | 2
70 | A | 1
50 | A | 2
----------------------------
我只想得到。
Sum A=170(type-1) SUMA=50(type-2) an Sum B=120(type-2)
Ref:在我之前的问题中,我在单列Group by in DataTable Column sum中得到了答案。
发布于 2011-10-28 22:04:29
您可以按匿名类型进行分组:
var result = from r in dt.AsEnumerable()
group r by new { Group = r["Group"], Type = r["Type"] } into g
select new { Group = g.Key.Group,
Type = g.Key.Type,
Sum = g.Sum(x => Convert.ToInt32(x["Rate"])) };
foreach (var r in result)
{
Console.WriteLine("Group {0}, Type {1}, Sum {2}", r.Group, r.Type, r.Sum);
}
https://stackoverflow.com/questions/7927538
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