JD2022-TU1/main/tools/services/JD.MapFileFontReader.Service/EPPlusCsvDataReader.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using OfficeOpenXml;

namespace JD.MapFileFontReader.Service
{
    public class EPPlusCsvDataReader : ICsvDataReader
    {
        /// <summary>
        /// Returns the data of the specified worksheet as a CsvData structure.
        /// </summary>
        public CsvData FromExcelFile(string filePath, string worksheetName)
        {
            if (!File.Exists(filePath)) throw new FileNotFoundException(filePath);

            var result = new CsvData();

            using (var package = new ExcelPackage(new FileInfo(filePath)))
            {
                //Get the Worksheet containing the data
                var ws = package.Workbook.Worksheets.FirstOrDefault(x => x.Name == worksheetName);

                // No worksheet -> ERROR
                if (ws == null)
                {
                    throw new Exception(
                        $"Cannot find worksheet {worksheetName} in excel {Path.GetFileName(filePath)}, " +
                        $"found only '{string.Join(", ", package.Workbook.Worksheets)}'");
                }

                if (ws.Dimension == null) return result;

                // Add the column names as they are in the first row
                for (int j = ws.Dimension.Start.Column; j < ws.Dimension.Columns; j++)
                {
                    result.ColumnNames.Add(ws.Cells[ws.Dimension.Start.Row, j].Text.Replace(" ", "_"));
                }

                // Get all cells grouped row by row (excluding the first row)
                for (int i = ws.Dimension.Start.Row + 1; i < ws.Dimension.Rows; i++)
                {
                    List<string> line = new List<string>();

                    for (int j = ws.Dimension.Start.Column; j < ws.Dimension.Columns; j++)
                    {
                        using (var row = ws.Cells[i, j])
                        {
                            line.Add(row.Text);
                        }
                    }

                    // Add the line as data rows
                    result.Rows.Add(new CsvData.Row(result.ColumnNames, line));
                }
                
                ws.Dispose();

                return result;
            }
        }
    }
}