列表组或排序

Question

我试图在Xamarin上使用c#程序对列表进行分组。

列出EList；

样本数据是

ExpList(项目，dop，值)

杂货店01/03/2019 1000

04/03/2019 250

杂货店01/04/2019 500

电影02/03/2018 550

02/05/2019 550

我想按项目名称对列表进行分组，并需要计算其总价值。即。

将列表分组

杂货店01/03/2019 1000

杂货店01/04/2019 500

04/03/2019 250

02/05/2019 550

电影02/03/2018 550

计算

我想要一些小组的信息，如下所示

组项目总数为3

食品杂货数乘以2，值为1500。

衣服数量2倍，价值800件

电影次数1和值为550

Answer 1

请参阅以下代码

public class People
{
    public string Name { get; set; }
    public string Date { get; set; }
    public double Value { get; set; }
}


List<People> peopleList = new List<People>()
        {
            new People { Name="grocery ",Date="01/03/2019",Value=1000 },
            new People { Name="clothes ",Date="02/03/2019",Value=250 },
            new People { Name="grocery ",Date="04/03/2019",Value=500 },
            new People { Name="clothes ",Date="01/02/2019",Value=550 },
            new People { Name="movie ",Date="03/03/2019",Value=550 },

        };


var groupList = peopleList.GroupBy(x => x.Name).Select(x => new { name = x.Key,Total=x.Sum(y=>y.Value),Num=x.Distinct().Count() }).Distinct().ToList();

Console.WriteLine("Total group Items is "+groupList.Count() );

foreach(var item in groupList)
{
  Console.WriteLine(item.name + " Number of times "+ item.Num + " and Value is " + item.Total);
}