【C# sharp Linq】Groupbyメソッドのグループ化項目を複数指定する方法

2024年1月22日

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今回のテーマ

こんばんは、サルモリです。

今回のテーマは下記の記事について書いていきます。

今回のテーマ

グループ化する項目を複数指定する方法

今回はグループ化する項目を複数指定する方法について記述していきます。

GroupByメソッドの使用方法について、下記の記事に書いてあります。

CHECK

: 【C# sharp Linq】GroupByを使ってグループ化しよう。

ChatGPTのAPIを使わずに自動化することが可能です。下記の本を読めば、ChatGPT4でも料金掛からずに自動化できます！KindleUnlimited会員であれば無料で読めます。今回のテーマ ...

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グループ化する項目を複数指定する方法を学ぼう！

サルモリ

他のLinqの記事についてはこちら

今回使用するクラス

今回使用するクラスです。今回もロボットクラスを使用します。

    class Robot
    {
        string name, color,maker;
        int strength;
        public Robot(string _name,string _color,int _strength,string _maker)
        {
            name = _name;
            color = _color;
            strength = _strength;
            maker = _maker;
        }
        public String Name
        {
            get { return name; }
        }
        public String Color
        {
            get { return color; }
        }
        
        public int Strength
        {
            get { return strength; }
        }
        public String Maker
        {
            get { return maker; }
        }
    }
}

class Robot

{

string name, color,maker;

int strength;

public Robot(string _name,string _color,int _strength,string _maker)

{

name = _name;

color = _color;

strength = _strength;

maker = _maker;

}

public String Name

{

get { return name; }

}

public String Color

{

get { return color; }

}

public int Strength

{

get { return strength; }

}

public String Maker

{

get { return maker; }

}

複数項目でグループ化する方法

早速、複数項目でグループ化するソースコードを書いていきます。

色と作成者別でグループ化をしてみます。

色と作成者別でグループ化を行う方法

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

namespace ConsoleApp2
{
    class Program
    {
        static void Main(string[] args)
        {
            List<Robot> robotlist = new List<Robot>();
            robotlist.Add(new Robot("Rockman", "Blue", 4,"Dr Light"));
            robotlist.Add(new Robot("Fireman", "Red", 3,"Dr Wily"));
            robotlist.Add(new Robot("Iceman", "Blue", 3, "Dr Wily"));
            robotlist.Add(new Robot("Elecman", "Yellow", 4, "Dr Wily"));
            robotlist.Add(new Robot("Roll", "Pink", 1, "Dr Light"));
            robotlist.Add(new Robot("Airman", "Blue", 2, "Dr Wily"));
            robotlist.Add(new Robot("Woodman", "Green", 2, "Dr Wily"));
            robotlist.Add(new Robot("Quickman", "Red", 5, "Dr Wily"));
            robotlist.Add(new Robot("Shadowman", "Blue", 5, "Dr Wily"));
            robotlist.Add(new Robot("Bubbleman", "Green", 3, "Dr Wily"));

            var groupcolormakerlist = robotlist.GroupBy(x => new { x.Color, x.Maker }).ToList();
            foreach (var colormakerlist in groupcolormakerlist)
            {
                foreach (var item in colormakerlist)
                {
                    Console.WriteLine("Color:" + item.Color + " Maker:" + item.Maker + "Name:" + item.Name);
                }
                Console.WriteLine("---------------------------------------------");
            }
        }
    }
}

using System;

using System.Collections.Generic;

using System.Linq;

namespace ConsoleApp2

{

class Program

{

static void Main(string[] args)

{

List<Robot> robotlist = new List<Robot>();

robotlist.Add(new Robot("Rockman", "Blue", 4,"Dr Light"));

robotlist.Add(new Robot("Fireman", "Red", 3,"Dr Wily"));

robotlist.Add(new Robot("Iceman", "Blue", 3, "Dr Wily"));

robotlist.Add(new Robot("Elecman", "Yellow", 4, "Dr Wily"));

robotlist.Add(new Robot("Roll", "Pink", 1, "Dr Light"));

robotlist.Add(new Robot("Airman", "Blue", 2, "Dr Wily"));

robotlist.Add(new Robot("Woodman", "Green", 2, "Dr Wily"));

robotlist.Add(new Robot("Quickman", "Red", 5, "Dr Wily"));

robotlist.Add(new Robot("Shadowman", "Blue", 5, "Dr Wily"));

robotlist.Add(new Robot("Bubbleman", "Green", 3, "Dr Wily"));

var groupcolormakerlist = robotlist.GroupBy(x => new { x.Color, x.Maker }).ToList();

foreach (var colormakerlist in groupcolormakerlist)

{

foreach (var item in colormakerlist)

{

Console.WriteLine("Color:" + item.Color + " Maker:" + item.Maker + "Name:" + item.Name);

}

Console.WriteLine("---------------------------------------------");

}

 result
Color:Blue Maker:Dr LightName:Rockman
---------------------------------------------
Color:Red Maker:Dr WilyName:Fireman
Color:Red Maker:Dr WilyName:Quickman
---------------------------------------------
Color:Blue Maker:Dr WilyName:Iceman
Color:Blue Maker:Dr WilyName:Airman
Color:Blue Maker:Dr WilyName:Shadowman
---------------------------------------------
Color:Yellow Maker:Dr WilyName:Elecman
---------------------------------------------
Color:Pink Maker:Dr LightName:Roll
---------------------------------------------
Color:Green Maker:Dr WilyName:Woodman
Color:Green Maker:Dr WilyName:Bubbleman
---------------------------------------------

Groupbyメソッド内で色と作成者の2つの項目を生成することでグループ化出来ていますね。

上記のやり方ともう1つ複数項目のグループ化を行う方法があるので、紹介したいと思います。

複数項目でグループ化する方法（タプルを利用する方法）

もう一つのやり方はタプルを使用する方法です。Groupby句で2つ項目を生成した箇所をタプルに置き換えるだけです。

早速、やってみましょう。

タプルについては下記の記事が分かりやすいと思います。

こちらもCHECK

: 【C# sharp】タプルを使用して2つの値を返す方法

ChatGPTのAPIを使わずに自動化することが可能です。下記の本を読めば、ChatGPT4でも料金掛からずに自動化できます！KindleUnlimited会員であれば無料で読めます。今回のテーマ ...

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色と作成者でグループ化を行う方法（タプルを利用する方法）

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

namespace ConsoleApp2
{
    class Program
    {
        static void Main(string[] args)
        {
            List<Robot> robotlist = new List<Robot>();
            robotlist.Add(new Robot("Rockman", "Blue", 4,"Dr Light"));
            robotlist.Add(new Robot("Fireman", "Red", 3,"Dr Wily"));
            robotlist.Add(new Robot("Iceman", "Blue", 3, "Dr Wily"));
            robotlist.Add(new Robot("Elecman", "Yellow", 4, "Dr Wily"));
            robotlist.Add(new Robot("Roll", "Pink", 1, "Dr Light"));
            robotlist.Add(new Robot("Airman", "Blue", 2, "Dr Wily"));
            robotlist.Add(new Robot("Woodman", "Green", 2, "Dr Wily"));
            robotlist.Add(new Robot("Quickman", "Red", 5, "Dr Wily"));
            robotlist.Add(new Robot("Shadowman", "Blue", 5, "Dr Wily"));
            robotlist.Add(new Robot("Bubbleman", "Green", 3, "Dr Wily"));

            var groupcolormakerlist = robotlist.GroupBy(x => (x.Color, x.Maker)).ToList();
            foreach (var colormakerlist in groupcolormakerlist)
            {
                foreach (var item in colormakerlist)
                {
                    Console.WriteLine("Color:" + item.Color + " Maker:" + item.Maker + "Name:" + item.Name);
                }
                Console.WriteLine("---------------------------------------------");
            }
        }
    }
}

using System;

using System.Collections.Generic;

using System.Linq;

namespace ConsoleApp2

{

class Program

{

static void Main(string[] args)

{

List<Robot> robotlist = new List<Robot>();

robotlist.Add(new Robot("Rockman", "Blue", 4,"Dr Light"));

robotlist.Add(new Robot("Fireman", "Red", 3,"Dr Wily"));

robotlist.Add(new Robot("Iceman", "Blue", 3, "Dr Wily"));

robotlist.Add(new Robot("Elecman", "Yellow", 4, "Dr Wily"));

robotlist.Add(new Robot("Roll", "Pink", 1, "Dr Light"));

robotlist.Add(new Robot("Airman", "Blue", 2, "Dr Wily"));

robotlist.Add(new Robot("Woodman", "Green", 2, "Dr Wily"));

robotlist.Add(new Robot("Quickman", "Red", 5, "Dr Wily"));

robotlist.Add(new Robot("Shadowman", "Blue", 5, "Dr Wily"));

robotlist.Add(new Robot("Bubbleman", "Green", 3, "Dr Wily"));

var groupcolormakerlist = robotlist.GroupBy(x => (x.Color, x.Maker)).ToList();

foreach (var colormakerlist in groupcolormakerlist)

{

foreach (var item in colormakerlist)

{

Console.WriteLine("Color:" + item.Color + " Maker:" + item.Maker + "Name:" + item.Name);

}

Console.WriteLine("---------------------------------------------");

}

 result
Color:Blue Maker:Dr LightName:Rockman
---------------------------------------------
Color:Red Maker:Dr WilyName:Fireman
Color:Red Maker:Dr WilyName:Quickman
---------------------------------------------
Color:Blue Maker:Dr WilyName:Iceman
Color:Blue Maker:Dr WilyName:Airman
Color:Blue Maker:Dr WilyName:Shadowman
---------------------------------------------
Color:Yellow Maker:Dr WilyName:Elecman
---------------------------------------------
Color:Pink Maker:Dr LightName:Roll
---------------------------------------------
Color:Green Maker:Dr WilyName:Woodman
Color:Green Maker:Dr WilyName:Bubbleman
---------------------------------------------

先ほどと同様に色と作成者別に出力されましたね！

タプルを使用して、2項目のグループ分けをしてみよう

早速、タプルで2項目指定してグループ分けしてみましょう。タプルとGroupbyの組み合わせの素晴らしさを味わって下さい。

この素晴らしさを感じてほしいので、いつも以上にロボットの追加を頑張りました。

強さはサルモリの主観で設定しています！！（異論は認める！）

まずはメーカー、色別で分けてみましょう！！

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

class Program
{
    static void Main(string[] args)
    {
        List<Robot> robotlist = new List<Robot>();
        robotlist.Add(new Robot("Rockman", "Dr Light", "Blue", 1, 5));
        robotlist.Add(new Robot("Rollchan", "Dr Light", "Pink", 1, 1));
        robotlist.Add(new Robot("Heatman", "Dr Wily", "Red", 2, 2));
        robotlist.Add(new Robot("Fireman", "Dr Wily", "Red", 1, 3));
        robotlist.Add(new Robot("Iceman", "Dr Wily", "Blue", 1, 4));
        robotlist.Add(new Robot("Quickman", "Dr Wily", "Red", 2, 5));
        robotlist.Add(new Robot("Airman", "Dr Wily", "Blue", 2, 3));
        robotlist.Add(new Robot("Shadowman", "Dr Wily", "Blue", 3, 5));
        robotlist.Add(new Robot("Snakeman", "Dr Wily", "Green", 3, 3));
        robotlist.Add(new Robot("Woodman", "Dr Wily", "Green", 2, 3));
        robotlist.Add(new Robot("Sparkman", "Dr Wily", "Red", 3, 4));
        robotlist.Add(new Robot("Hardman", "Dr Wily", "Blue", 3, 4));
        robotlist.Add(new Robot("Flashman", "Dr Wily", "Blue", 2, 2));
        var robotslists = robotlist.GroupBy(n => (n.getMaker(),n.getColor()));
        foreach(var rlist in robotslists)
        {
            foreach(var robot in rlist)
            {
                Console.WriteLine("Name:" + robot.getName() + " Maker:" + robot.getMaker() 
                    + " Color:" + robot.getColor());
            }
            Console.WriteLine("----------------------------------------");
        }
    }
}

using System;

using System.Collections.Generic;

using System.Linq;

class Program

{

static void Main(string[] args)

{

List<Robot> robotlist = new List<Robot>();

robotlist.Add(new Robot("Rockman", "Dr Light", "Blue", 1, 5));

robotlist.Add(new Robot("Rollchan", "Dr Light", "Pink", 1, 1));

robotlist.Add(new Robot("Heatman", "Dr Wily", "Red", 2, 2));

robotlist.Add(new Robot("Fireman", "Dr Wily", "Red", 1, 3));

robotlist.Add(new Robot("Iceman", "Dr Wily", "Blue", 1, 4));

robotlist.Add(new Robot("Quickman", "Dr Wily", "Red", 2, 5));

robotlist.Add(new Robot("Airman", "Dr Wily", "Blue", 2, 3));

robotlist.Add(new Robot("Shadowman", "Dr Wily", "Blue", 3, 5));

robotlist.Add(new Robot("Snakeman", "Dr Wily", "Green", 3, 3));

robotlist.Add(new Robot("Woodman", "Dr Wily", "Green", 2, 3));

robotlist.Add(new Robot("Sparkman", "Dr Wily", "Red", 3, 4));

robotlist.Add(new Robot("Hardman", "Dr Wily", "Blue", 3, 4));

robotlist.Add(new Robot("Flashman", "Dr Wily", "Blue", 2, 2));

var robotslists = robotlist.GroupBy(n => (n.getMaker(),n.getColor()));

foreach(var rlist in robotslists)

{

foreach(var robot in rlist)

{

Console.WriteLine("Name:" + robot.getName() + " Maker:" + robot.getMaker()

+ " Color:" + robot.getColor());

}

Console.WriteLine("----------------------------------------");

}

 出力結果
Name:Rockman Maker:Dr Light Color:Blue
----------------------------------------
Name:Rollchan Maker:Dr Light Color:Pink
----------------------------------------
Name:Heatman Maker:Dr Wily Color:Red
Name:Fireman Maker:Dr Wily Color:Red
Name:Quickman Maker:Dr Wily Color:Red
Name:Sparkman Maker:Dr Wily Color:Red
----------------------------------------
Name:Iceman Maker:Dr Wily Color:Blue
Name:Airman Maker:Dr Wily Color:Blue
Name:Shadowman Maker:Dr Wily Color:Blue
Name:Hardman Maker:Dr Wily Color:Blue
Name:Flashman Maker:Dr Wily Color:Blue
----------------------------------------
Name:Snakeman Maker:Dr Wily Color:Green
Name:Woodman Maker:Dr Wily Color:Green
----------------------------------------

凄く簡単ですよね！Groupbyでグループ別にしたい項目をタプルに設定するだけで出来てしまいます！素晴らしい！

robotlist.GroupBy(n => (n.getMaker(),n.getColor()));

1	robotlist.GroupBy(n => (n.getMaker(),n.getColor()));

シリーズ、強さ別にも分けてみましょう！

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

class Program
{
    static void Main(string[] args)
    {
        List<Robot> robotlist = new List<Robot>();
        robotlist.Add(new Robot("Rockman", "Dr Light", "Blue", 1, 5));
        robotlist.Add(new Robot("Rollchan", "Dr Light", "Pink", 1, 1));
        robotlist.Add(new Robot("Heatman", "Dr Wily", "Red", 2, 2));
        robotlist.Add(new Robot("Fireman", "Dr Wily", "Red", 1, 3));
        robotlist.Add(new Robot("Iceman", "Dr Wily", "Blue", 1, 4));
        robotlist.Add(new Robot("Quickman", "Dr Wily", "Red", 2, 5));
        robotlist.Add(new Robot("Airman", "Dr Wily", "Blue", 2, 3));
        robotlist.Add(new Robot("Shadowman", "Dr Wily", "Blue", 3, 5));
        robotlist.Add(new Robot("Snakeman", "Dr Wily", "Green", 3, 3));
        robotlist.Add(new Robot("Woodman", "Dr Wily", "Green", 2, 3));
        robotlist.Add(new Robot("Sparkman", "Dr Wily", "Red", 3, 4));
        robotlist.Add(new Robot("Hardman", "Dr Wily", "Blue", 3, 4));
        robotlist.Add(new Robot("Flashman", "Dr Wily", "Blue", 2, 2));
        var robotslists = robotlist.GroupBy(n => (n.getSeries(),n.getStrength()));
        foreach(var rlist in robotslists)
        {
            foreach(var robot in rlist)
            {
                Console.WriteLine("Name:" + robot.getName() + " Series:" + robot.getSeries() 
                    + " Strength:" + robot.getStrength());
            }
            Console.WriteLine("----------------------------------------");
        }
    }
}