ClosedXMLTest

ExcelRead.cs

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

namespace ClosedXMLTest
{
    class ExcelRead
    {
        // Excelファイルからインプットを読み込む
        static public Dictionary<string, List<string>> Read(string filePath, string sheetName)
        {
            Dictionary<string, List<string>> inputs = new Dictionary<string, List<string>>();

            var workbook = new XLWorkbook(filePath);
            var worksheet = workbook.Worksheet(sheetName);

            int inputStartRow = 2; // 入力の開始行
            int inputNameCol = 1;  // 各入力変数の名前を指定する列
            int inputValueStartCol = 5; // 各入力変数の値が開始する列

            // 名前が空白となるまで読み込む
            int r = inputStartRow;
            while (true)
            {
                string name = worksheet.Cell(r, inputNameCol).Value.ToString();
                if (name == string.Empty) break;

                // 値に空白があるまで読み込み、stringのリストとする
                int c = inputValueStartCol;
                List<string> values = new List<string>();
                while (true)
                {
                    string value = worksheet.Cell(r, c).Value.ToString();
                    if (value == string.Empty) break;
                    values.Add(value);
                    c++;
                }

                inputs.Add(name, values);
                r++;
            }

            return inputs;
        }

    }
}

ExcelWrite.cs

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

namespace ClosedXMLTest
{
    class ExcelWrite
    {
        // Excelファイルに結果を出力する
        public static void Write(string filepath, string sheetName, List<Record<double>> records)
        {
            var workbook = new XLWorkbook();
            var ws = workbook.Worksheets.Add(sheetName);

            int outputStartRow = 2; // 入力の開始行
            int outputNameCol = 1;  // 各入力変数の名前を指定する列
            int outputValueStartCol = 5; // 各入力変数の値が開始する列

            for (int i = 0; i < records.Count; i++)
            {
                Record<double> record = (Record<double>)records[i];
                ws.Cell(i + outputStartRow, outputNameCol).Value = record.Name;
                for (int e = 0; e < record.Values.Length; e++)
                {
                    ws.Cell(i + outputStartRow, e + outputValueStartCol ).Value = record.Values[e];
                }
            }

            ws.Column(outputNameCol).AdjustToContents();
            workbook.SaveAs(filepath);
        }
    
    }

    // 名前と値（配列）の組
    public class Record<T>
    {
        public string Name;
        public T[] Values;

        public Record(string name, T[] values)
        {
            this.Name = name;
            this.Values = values;
        }
    }
}

Program.cs

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

namespace ClosedXMLTest
{
    class Program
    {
        static void Main(string[] args)
        {
            Dictionary<string, List<string>> inputs = ExcelRead.Read("Input.xlsm", "Input");
            List<string> keys = inputs.Keys.ToList();
            List<Record<double>> records = keys.Select(k => new Record<double>(k, inputs[k].Select(e => double.Parse(e)).ToArray())).ToList();
            ExcelWrite.Write("Output.xlsx", "Output", records);

        }
    }
}