C# - How to add an Excel Worksheet programmatically - Office XP / 2003

Question

I am just starting to fiddle with Excel via C# to be able to automate the creation, and addition to an Excel file.

I can open the file and update its data and move through the existing worksheets. My problem is how can I add new sheets?

I tried:

Excel.Worksheet newWorksheet;
newWorksheet = (Excel.Worksheet)excelApp.ThisWorkbook.Worksheets.Add(
                Type.Missing, Type.Missing, Type.Missing, Type.Missing);

But I get below COM Exception and my googling has not given me any answer.

Exception from HRESULT: 0x800A03EC Source is: "Interop.Excel"

I am hoping someone maybe able to put me out of my misery.

Answer 1

You need to add a COM reference in your project to the "Microsoft Excel 11.0 Object Library" - or whatever version is appropriate.

This code works for me:

private void AddWorksheetToExcelWorkbook(string fullFilename,string worksheetName)
{
    Microsoft.Office.Interop.Excel.Application xlApp = null;
    Workbook xlWorkbook = null;
    Sheets xlSheets = null;
    Worksheet xlNewSheet = null;

    try {
        xlApp = new Microsoft.Office.Interop.Excel.Application();

        if (xlApp == null)
            return;

        // Uncomment the line below if you want to see what's happening in Excel
        // xlApp.Visible = true;

        xlWorkbook = xlApp.Workbooks.Open(fullFilename, 0, false, 5, "", "",
                false, XlPlatform.xlWindows, "",
                true, false, 0, true, false, false);

        xlSheets = xlWorkbook.Sheets as Sheets;

        // The first argument below inserts the new worksheet as the first one
        xlNewSheet = (Worksheet)xlSheets.Add(xlSheets[1], Type.Missing, Type.Missing, Type.Missing);
        xlNewSheet.Name = worksheetName;

        xlWorkbook.Save();
        xlWorkbook.Close(Type.Missing,Type.Missing,Type.Missing);
        xlApp.Quit();
    }
    finally {
        Marshal.ReleaseComObject(xlNewSheet);
        Marshal.ReleaseComObject(xlSheets);
        Marshal.ReleaseComObject(xlWorkbook);
        Marshal.ReleaseComObject(xlApp);
        xlApp = null;
    }
}

Note that you want to be very careful about properly cleaning up and releasing your COM object references. Included in that StackOverflow question is a useful rule of thumb: "Never use 2 dots with COM objects". In your code; you're going to have real trouble with that. My demo code above does NOT properly clean up the Excel app, but it's a start!

Some other links that I found useful when looking into this question:

• Opening and Navigating Excel with C#
• How to: Use COM Interop to Create an Excel Spreadsheet (C# Programming Guide)
• How to: Add New Worksheets to Workbooks

According to MSDN

To use COM interop, you must have administrator or Power User security permissions.

Hope that helps.

Answer 2

Would like to thank you for some excellent replies. @AR., your a star and it works perfectly. I had noticed last night that the Excel.exe was not closing; so I did some research and found out about how to release the COM objects. Here is my final code:

using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;
using System.IO;
using Excel;

namespace testExcelconsoleApp
{
    class Program
    {
        private String fileLoc = @"C:\temp\test.xls";

        static void Main(string[] args)
        {
            Program p = new Program();
            p.createExcel();
        }

        private void createExcel()
        {
            Excel.Application excelApp = null;
            Excel.Workbook workbook = null;
            Excel.Sheets sheets = null;
            Excel.Worksheet newSheet = null;

            try
            {
                FileInfo file = new FileInfo(fileLoc);
                if (file.Exists)
                {
                    excelApp = new Excel.Application();
                    workbook = excelApp.Workbooks.Open(fileLoc, 0, false, 5, "", "",
                                                        false, XlPlatform.xlWindows, "",
                                                        true, false, 0, true, false, false);

                    sheets = workbook.Sheets;

                    //check columns exist
                    foreach (Excel.Worksheet sheet in sheets)
                    {
                        Console.WriteLine(sheet.Name);
                        sheet.Select(Type.Missing);

                        System.Runtime.InteropServices.Marshal.ReleaseComObject(sheet);
                    }

                    newSheet = (Worksheet)sheets.Add(sheets[1], Type.Missing, Type.Missing, Type.Missing);
                    newSheet.Name = "My New Sheet";
                    newSheet.Cells[1, 1] = "BOO!";

                    workbook.Save();
                    workbook.Close(null, null, null);
                    excelApp.Quit();
                }
            }
            finally
            {
                System.Runtime.InteropServices.Marshal.ReleaseComObject(newSheet);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(sheets);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(excelApp);

                newSheet = null;
                sheets = null;
                workbook = null;
                excelApp = null;

                GC.Collect();
            }
        }
    }
}

Thank you for all your help.

Answer 3

Another "Up Tick" for AR..., but if you don't have to use interop I would avoid it altogether. This product is actually quite interesting: http://www.clearoffice.com/ and it provides a very intuitive, fully managed, api for manipulation excel files and seems to be free. (at least for the time being) SpreadSheetGear is also excellent but pricey.

my two cents.

Answer 4

Do not forget to include Reference to Microsoft Excel 12.0/11.0 object Library

using Excel = Microsoft.Office.Interop.Excel;
// Include this Namespace

Microsoft.Office.Interop.Excel.Application xlApp = null;
Excel.Workbook xlWorkbook = null;
Excel.Sheets xlSheets = null;
Excel.Worksheet xlNewSheet = null;
string worksheetName ="Sheet_Name";
object readOnly1 = false;

object isVisible = true;

object missing = System.Reflection.Missing.Value;

try
{
    xlApp = new Microsoft.Office.Interop.Excel.Application();

    if (xlApp == null)
        return;

    // Uncomment the line below if you want to see what's happening in Excel
    // xlApp.Visible = true;

    xlWorkbook = xlApp.Workbooks.Open(@"C:\Book1.xls", missing, readOnly1, missing, missing, missing, missing, missing, missing, missing, missing, isVisible, missing, missing, missing);

    xlSheets = (Excel.Sheets)xlWorkbook.Sheets;

    // The first argument below inserts the new worksheet as the first one
    xlNewSheet = (Excel.Worksheet)xlSheets.Add(xlSheets[1], Type.Missing, Type.Missing, Type.Missing);
    xlNewSheet.Name = worksheetName;

    xlWorkbook.Save();
    xlWorkbook.Close(Type.Missing, Type.Missing, Type.Missing);
    xlApp.Quit();
}
finally
{
    System.Runtime.InteropServices.Marshal.ReleaseComObject(xlNewSheet);
    System.Runtime.InteropServices.Marshal.ReleaseComObject(xlSheets);
    System.Runtime.InteropServices.Marshal.ReleaseComObject(xlWorkbook);
    System.Runtime.InteropServices.Marshal.ReleaseComObject(xlApp);
    //xlApp = null;
}

Answer 5

You can use OLEDB to create and manipulate Excel files. See this question for links and samples.

Answer 6

Here are a couple things I figured out:

1. You can't open more than one instance of the same object at the same time. For Example if you instanciate a new excel sheet object called xlsheet1 you have to release it before creating another excel sheet object ex xlsheet2. It seem as COM looses track of the object and leaves a zombie process on the server.

2. Using the open method associated with excel.workbooks also becomes difficult to close if you have multiple users accessing the same file. Use the Add method instead, it works just as good without locking the file. eg. xlBook = xlBooks.Add("C:\location\XlTemplate.xls")

3. Place your garbage collection in a separate block or method after releasing the COM objects.

Answer 7

COM is definitely not a good way to go. More specifically, it's a no go if you're dealing with web environment...

I've used with success the following open source projects:

• ExcelPackage for OOXML formats (Office 2007)

• NPOI for .XLS format (Office 2003)

Take a look at these blog posts:

Creating Excel spreadsheets .XLS and .XLSX in C#

NPOI with Excel Table and dynamic Chart

Answer 8

This is what i used to add addtional worksheet

Workbook workbook = null;
Worksheet worksheet = null;

workbook = app.Workbooks.Add(1);
workbook.Sheets.Add();

Worksheet additionalWorksheet = workbook.ActiveSheet;

Answer 9

I had a similar problem application-level add-in in VSTO, the exception HRESULT: 0x800A03EC when adding new sheet.

The error code 0x800A03EC (or -2146827284) means NAME_NOT_FOUND; in other words, you've asked for something, and Excel can't find it.

Dominic Zukiewicz @ Excel error HRESULT: 0x800A03EC while trying to get range with cell's name

Then I finally realized ThisWorkbook triggered the exception. ActiveWorkbook went OK.

Excel.Worksheet newSheetException = Globals.ThisAddIn.Application.ThisWorkbook.Worksheets.Add(Type.Missing, sheet, Type.Missing, Type.Missing);
Excel.Worksheet newSheetNoException = Globals.ThisAddIn.Application.ActiveWorkbook.Worksheets.Add(Type.Missing, sheet, Type.Missing, Type.Missing);