将 .xlsx 文件转换为 .xls(97-2003) 工作簿 C#

Question

i am trying to convert .xlsx file to .xls(97-2003) workbook. which might have around 1000 rows n more . is there any nuget package that i can use which is free? i have tried using Microsoft.Office.Interop.Excel but it didnt work out on IIS.

    string sourceFileName = appSettings.ImageDirectory + "Report.xlsx";
    string DestFileName = appSettings.ImageDirectory + "Report.xls";
    object oMissing = Type.Missing;
    var app = new Microsoft.Office.Interop.Excel.Application();
    var wb = app.Workbooks.Open(sourceFileName, oMissing, oMissing,
                                    oMissing, oMissing, oMissing, oMissing, 
    oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, 
    oMissing);
    wb.Application.DisplayAlerts = false;
    wb.SaveAs(DestFileName , 
    Microsoft.Office.Interop.Excel.XlFileFormat.xlExcel8, Type.Missing, 
    Type.Missing, Type.Missing, Type.Missing, 
    Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlExclusive, 
    Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);
    app.Quit();
    string fullPath = appSettings.ReportFolderPath + "/Report.xls"; 
    return Json(new { path = fullPath, errorMessage = "" });

Answer 1

As far as I know, you couldn't use Microsoft.Office.Interop.Excel on a server where Excel is not installed.

Microsoft.Office.Interop.Excel.dll is just a translator (called an Interop Assembly) to help you talk to Excel.

You could try to use ClosedXML to achieve your requirement.