C# 如何按列表合并分组和无键值求和

例如，我有一个分组列表：

List<Cl> list = new List<Cl>()
        {
            new Cl() { vi = 1, vs = "q", am = 20 },
            new Cl() { vi = 1, vs = "w", am = 30 },
            new Cl() { vi = 2, vs = "w", am = 40 },
            new Cl() { vi = 1, vs = "q", am = 50 }
        };
groups = list.GroupBy(b => new { b.vi, b.vs }).ToList();

不使用字典或KeyValuePair就可以实现它吗

---

我将非常感谢您的帮助。

您可以尝试以下方法：

class Key
{
    public int Vi { get; set; }
    public string Vs { get; set; }

    public Key(int vi, string vs)
    {
        Vi = vi;
        Vs = vs;
    }
}

var result = groups = list.GroupBy(b => new { b.vi, b.vs })
                          .Select(gr=> new { Key = Key(gr.vi,gr.vs)
                                           , Value = gr.Sum(x=>x.am)})
                          .ToList();

var groups = list.GroupBy(b => new { b.vi, b.vs })
                 .Select(g => new { g.Key, am = g.Sum(s => s.am)})
                 .ToList();

首先

GroupBy（）

，然后

Sum（）

向上计算各组的

am

值

List<Cl> groups = list.GroupBy(b => new { b.vi, b.vs })
                      .Select(x => new Cl() { vi = x.Key.vi,
                                              vs = x.Key.vs, 
                                              am = x.Sum(y => y.am) }).ToList();

List groups=List.GroupBy（b=>new{b.vi，b.vs}）
.Select（x=>newcl（）{vi=x.Key.vi，
vs=x.Key.vs，
am=x.Sum（y=>y.am）}）.ToList（）；

像这样尝试：

class Key
{
    public int Vi { get; set; }
    public string Vs { get; set; }

    public Key(int vi, string vs)
    {
        Vi = vi;
        Vs = vs;
    }
}

var result = groups = list.GroupBy(b => new { b.vi, b.vs })
                          .Select(gr=> new { Key = Key(gr.vi,gr.vs)
                                           , Value = gr.Sum(x=>x.am)})
                          .ToList();

var groups = list.GroupBy(b => new { b.vi, b.vs })
                 .Select(g => new { g.Key, am = g.Sum(s => s.am)})
                 .ToList();