What is the easiest way to count .xlsx workbook sheets using c#, NPOI and an XSSF workbook?

Question

I am trying to count the number of sheets in a workbook. The workbook is created using NPOI and there doesn't seem to be a way to count the amount of sheets using the C# version of NPOI?

This is a really tricky thing to both explain and show... But I will give it a try.

What I am trying to do is having an existing excel-file as a template for statistics. This existing excel-file can have different amounts of templates and I need to be able to count these templates to know where to place my new sheets and edit their names.

The sender of the data only has to chose which template-sheet should be filled with which data, and I will then remove the template-sheets from the workbook after all data has been inserted.

What I have tried:

I have read the documentation and searched for information and have tried the following approaches:

• getNumberOfSheets - How to know number of sheets in a workbook?

Problem with this approach: The C# version of NPOI doesn't seem to have getNumberOfSheets.

• Convert found row-counters into sheet-counters - NPOI - Get excel row count to check if it is empty

Can't really recreate the code to work for sheets as the functionality for sheets and rows are too different.

var sheetIndex = 0;
foreach (var sheet in requestBody.Sheets)
{
    if (sheet.TemplateNumber == "")
    {
       sheetTemplate = templateWorkbook.CreateSheet(sheet.Name);
    }
    else
    {
        sheetTemplate = templateWorkbook.CloneSheet(Convert.ToInt32(sheet.SheetTemplate));
        if (!templates.Contains(Convert.ToInt32(sheet.SheetTemplate)))
        {
            templates.Add(Convert.ToInt32(sheet.SheetTemplate));
        }

// Do math's to make sure we add the name to the newly created sheet further down the code (I need to actual index here)
    }
// Insert statistics 

//After inserting statistics:
    workingCopy.SetSheetName(sheetIndex, sheet.Name);

    foreach (var template in templates)
    {
        workingCopy.RemoveSheetAt(template);
    }
}

Answer 1

You can get number of sheets from NumberOfSheets property in XSSFWorkbook class.