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按多行/多列分组以创建复合“视图”

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我定义了一个上下文，该上下文公开了一个带有“结果”子集合的“记录”。每个结果都有一个ResultType，每个Record可以具有每种类型的多个结果； 

public class Record : Entity<int>
{
    public int Count { get; set; }

    public virtual List<Result> Results { get; set; } = new List<Result>();
}

public class Result : Entity<int>
{
    public int RecordId { get; set; }

    public Record Record { get; set; }

    public ResultType ResultType { get; set; }

    public string Value1 { get; set; }

    public string Value2 { get; set; }
}

我希望返回由ResultType按Result.Value1和Result.Value2的组合数据分组/求和的所有记录的列表，总和为Record.Count。

例如

Record 1 : Count - 10
 - Result (ResultType = 1,Value1 = "value1",Value2 = "value2")
 - Result (ResultType = 1,Value1 = "other1",Value2 = "other2")
 - Result (ResultType = 0,Value1 = "a",Value2 = "b")

Record 2 : Count - 10
 - Result (ResultType = 1,Value2 = "b")

Record 3 : Count - 50
 - Result (ResultType = 1,Value2 = "value2)
 - Result (ResultType = 0,Value2 = "b)

将给出2行，并带有结果的组合值； 

Count = 20,CombinedResultType0 = "a#b",CombinedResultType1 = "value1|value2,other1|other2"
Count = 50,CombinedResultType1 = "value1|value2"

我正在使用Linq to Entities，但无法弄清楚如何对单个或多个语句进行隐式化和分组。目前，我通过在插入数据时创建数据的复合视图（CombinedResultType0 / 1）并将其添加到Record中，然后仅按该列分组而不存储每个“结果”，来解决此问题。不幸的是，这不能为我提供一种直接查询结果的干净方法。

kx287973135 回答：按多行/多列分组以创建复合“视图”

尝试以下操作：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            List<Record> records = new List<Record>() {
                new Record() {
                    Count = 10,Results = new List<Result>() {
                        new Result() { ResultType = ResultType.One,Value1 = "value1",Value2 = "value2"},new Result() {ResultType = ResultType.One,Value1 = "other1",Value2 = "other2"},new Result() {ResultType = ResultType.Zero,Value1 = "a",Value2 = "b"}
                    }
                },new Record() {
                    Count = 10,Results = new List<Result>() {
                       new Result() {ResultType = ResultType.One,new Record() {
                    Count = 50,Value2 = "b"}
                    }
                }
            };

            var temp = records.Select(x => new { 
                count = x.Count,CombinedResultType0 = x.Results.Where(y => y.ResultType == ResultType.Zero).Select(z => z.Value1 + "#" + z.Value2).FirstOrDefault(),CombinedResultType1 = string.Join(",",x.Results.Where(y => y.ResultType == ResultType.One).Select(z => z.Value1 + "|" + z.Value2))
            }).ToList();

            var results = temp.GroupBy(x => new { zero = x.CombinedResultType0,one = x.CombinedResultType1 })
                .Select(x => new { count = x.Sum(y => y.count),CombinedResultType0 = x.Key.zero,CombinedResultType1 = x.Key.one })
                .ToList();
        }
    }

    public class Record 
    {
        public int Count { get; set; }
        public virtual List<Result> Results { get; set; }
    }
    public class Result
    {
        public int RecordId { get; set; }
        public Record Record { get; set; }
        public ResultType ResultType { get; set; }
        public string Value1 { get; set; }
        public string Value2 { get; set; }
    }
    public enum ResultType
    {
        Zero,One
    }
}
c#entity-frameworklinq
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