Question

我有以下列表：

 mat.Add(new Material() { ID = 1, ProdName = "Cylinder", Weight=23, Discontinued='N'  });
 mat.Add(new Material() { ID = 2, ProdName = "Gas", Weight = 25, Discontinued='N' });
mat.Add(new Material() { ID = 3, ProdName = "Match", Weight = 23, Discontinued='N' });

我想要一个结果：

2 Products have Weight 23 and Discontinued N
1 Product have Weigth 25 Discontinued N

Answer 1

目前尚不清楚你实际上在分组的是什么 - 重量和是否已停止状态？如果是这样，你可以这样做：

var query = mat.GroupBy(material => 
                        new { material.Weight, material.Discontinued });

foreach (var result in query)
{
    Console.WriteLine("{0} products have {1}", result.Count(), result.Key);
}

Answer 2

知道了！

.GroupBy(re => new { re.Weight, re.Discontinued })
           .Select(grp => new { CXXX = group.Key, Count = grp.Count()

Answer 3

“只是”按重量分组并停止使用。

像这样的东西： var result = mat.GroupBy（a =＆gt; new {a.Weight，a.Discontinued}）。选择（b =＆gt; new b.Key.Weight，b.Key.Discontinued，Count = b.Count（）} ）;

用sum对数据进行分组

3 个答案: