how to read comments of excel sheet in c#

Question

i am trying to read the comments from excel sheet but unable to do so. Please help. Thanks in advance. my code is as follows-

  Excel.Application appExl;
  Excel.Workbook workbook;
  Excel.Worksheet NwSheet;
  Excel.Range ShtRange;
  appExl = new Excel.Application();
  workbook = appExl.Workbooks.Open(Server.MapPath("~/" + System.Configuration.ConfigurationManager.AppSettings["ExcelFile"] + fileName), Missing.Value, Missing.Value,
  Missing.Value, Missing.Value, Missing.Value, Missing.Value, Missing.Value, Missing.Value,
  Missing.Value, Missing.Value, Missing.Value, Missing.Value, Missing.Value, Missing.Value);
  NwSheet = (Excel.Worksheet)workbook.Sheets.get_Item(1);
  string obj = NwSheet.Range[0].Comment.Text;    

Answer 1

You basically had it, but as Wimbo said, 0 isn't a valid range.

When interoping with Office from .Net, arrays always start at one. A range is a 2D array, so once you have a range, the top left cell in that Range is accessed like so:

using Excel = Microsoft.office.Interop.Excel;
Excel.Range range = worksheet.Cells[1,1];

To access the cell below the top left one, you would do this:

Excel.Range range = worksheet.Cells[2,1]; //It goes row, then column

To access the cell one to the right of the top left cell, you do this:

Excel.Range range = worksheet.Cells[1,2];

If you are working in .Net 4 or above, you don't need to specify the optional parameters (in otherwords you can drop all of the Missing.Value's). I'm guessing you want to get the comment in Cell A1 on Sheet 1 in a workbook, I would do this like so:

using System.Runtime.InteropServices;
using Excel = Microsoft.Office.Interop.Excel;

namespace ExcelComments
{
    class Program
    {
        static void Main()
        {
            var application = new Excel.Application();
            var workbook = application.Workbooks.Open(@"C:\Yada yada\workbook with comments.xlsx");
            Excel.Worksheet worksheet = workbook.Sheets[1];

            Excel.Range range = worksheet.Cells[1, 1];

            //Here is your comment as a string
            var myComment = range.Comment.Text();

            workbook.Close(false);
            application.Quit();

            Marshal.ReleaseComObject(application);
        }
    }
}