Read data from MS Excel

excel-reader.cs

/// <summary>
/// See https://coderwall.com/p/app3ya/read-excel-file-in-c
/// </summary>
namespace App
{
    using System;
    using System.Runtime.InteropServices;
    using Excel = Microsoft.Office.Interop.Excel;       //microsoft Excel 14 object in references-> COM tab

    public class Program
    {
        public static void Main(string[] args)
        {
            if (args.Length > 0)
            {
                GetExcelFile(args[0]);
            }
        }

        public static void GetExcelFile(string fileName)
        {
            //Create COM Objects. Create a COM object for everything that is referenced
            Excel.Application excelApplication = new Excel.Application();
            Excel.Workbook excelWorkbook = excelApplication.Workbooks.Open(fileName);
            Excel._Worksheet excelWorksheet = excelWorkbook.Sheets[1];
            Excel.Range excelRange = excelWorksheet.UsedRange;

            int rowCount = excelRange.Rows.Count;
            int colCount = excelRange.Columns.Count;

            //iterate over the rows and columns and print to the console as it appears in the file
            //excel is not zero based!!
            for (int i = 1; i <= rowCount; i++)
            {
                for (int j = 1; j <= colCount; j++)
                {
                    //new line
                    if (j == 1)
                    {
                        Console.Write("\r\n");
                    }

                    var cell = excelRange.Cells[i, j];
                    
                    //write the value to the console
                    if (cell != null && cell.Value2 != null)
                    {
                        Console.Write(cell.Value2.ToString() + "\t");
                        ////if (j == 4)
                        ////{
                        ////    cell.Value2 += 1;
                        ////}
                    }
                }
            }

            ////excelWorkbook.Save();

            //cleanup
            GC.Collect();
            GC.WaitForPendingFinalizers();

            //rule of thumb for releasing com objects:
            //  never use two dots, all COM objects must be referenced and released individually
            //  ex: [somthing].[something].[something] is bad

            //release com objects to fully kill excel process from running in the background
            Marshal.ReleaseComObject(excelRange);
            Marshal.ReleaseComObject(excelWorksheet);

            //close and release
            excelWorkbook.Close();
            Marshal.ReleaseComObject(excelWorkbook);

            //quit and release
            excelApplication.Quit();
            Marshal.ReleaseComObject(excelApplication);
        }
    }
}