CsvHelper for Excel is an extension that links 2 excellent libraries, CsvHelper and ClosedXml. It provides an implementation of ICsvParser and ICsvSerializer from CsvHelper that read and write to Excel using ClosedXml.

ExcelParser implements ICsvParser and allows you to specify the path of the workbook, pass an instance of XLWorkbook that you have already loaded, or a specific instance of IXLWorksheet to use as the data source.

When the path is passed to the constructor then the workbook loading and disposal is handled by the parser. By default the first worksheet is used as the data source.

using (var reader = new CsvReader(new ExcelParser("path/to/file.xlsx")))
{
    var people = reader.GetRecords<Person>();
}

When an instance of XLWorkbook is passed to the constructor then disposal will not be handled by the parser. By default the first worksheet is used as the data source.

using (var workbook = new XLWorkbook("path/to/file.xlsx", XLEventTracking.Disabled))
{
    // do stuff with the workbook
    using (var reader = new CsvReader(new ExcelParser(workbook)))
    {
        var people = reader.GetRecords<Person>();
    }
    // do other stuff with workbook
}

When an instance of IXLWorksheet is passed to the constructor then disposal will not be handled by the parser and the worksheet will be used as the data source.

using (var workbook = new XLWorkbook("path/to/file.xlsx", XLEventTracking.Disabled))
{
    var worksheet = workbook.Worksheets().First(sheet => sheet.Name == "Folk");
    using (var reader = new CsvReader(new ExcelParser(worksheet)))
    {
        var people = reader.GetRecords<Person>();
    }
}

All constructor options have overloads allowing you to specify your own CsvConfiguration, otherwise the default is used.

ExcelSerializer implements ICsvSerializer and, like ExcelParser, allows you to specify the path to which to (eventually) save the workbook, pass an instance of XLWorkbook that you have already created, or pass a specific instance of IXLWorksheet to use as the destination.

When the path is passed to the constructor the creation and disposal of both the workbook and worksheet (defaultly named "Export") as well as the saving of the workbook on dispose, is handled by the serialiser.

using (var writer = new CsvWriter(new ExcelSerializer("path/to/file.xlsx")))
{
    writer.WriteRecords(people);
}

When an instance of XLWorkbook is passed to the constructor the creation and disposal of a new worksheet (defaultly named "Export") is handled by the serialiser, but the workbook will not be saved.

using (var workbook = new XLWorkbook(XLEventTracking.Disabled))
{
    // do stuff with the workbook
    using (var writer = new CsvWriter(new ExcelSerializer(workbook)))
    {
        writer.WriteRecords(people);
    }
    // do other stuff with workbook
    workbook.SaveAs("path/to/file.xlsx");
}

When an instance of IXLWorksheet is passed to the constructor then the serialiser will not dispose or save anything.

using (var workbook = new XLWorkbook(XLEventTracking.Disabled))
{
    var worksheet = workbook.AddWorksheet("Folk");
    using (var writer = new CsvWriter(new ExcelSerializer(worksheet)))
    {
        writer.WriteRecords(people);
    }
    workbook.SaveAs("path/to/file.xlsx");
}

All constructor options have overloads allowing you to specify your own CsvConfiguration, otherwise the default is used.