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C#

ASP.NET-Core

Hi everyone, I have a sample excel template. I want to write the data from the database on this template. But I am facing such an error. I'm using NPOI library.

IWorkbook workbookMerged;

            using (var file = new FileStream(_importExportHelper.GetFilePath("EXCEL-TEMPLATE-NAME"), FileMode.Open, FileAccess.ReadWrite))
            {
                workbookMerged = new XSSFWorkbook(file); //here
            }


  public string GetFilePath(string source, string type = ".xlsx")
    {
        string sWebRootFolder = System.IO.Path.GetDirectoryName(Assembly.GetEntryAssembly().Location);

        var files = new DirectoryInfo(sWebRootFolder + @"\documents\").GetFiles(source + type, SearchOption.TopDirectoryOnly);

        return files.FirstOrDefault().ToString();
    }

What I have tried:

Hi everyone, I have a sample excel template. I want to write the data from the database on this template. But I am facing such an error. I'm using NPOI library.