I have a controller endpoint from which I want to generate a csv file and download it.

Currently I am using nuget CsvHelper and my code is like this:

var cc = new CsvConfiguration(new System.Globalization.CultureInfo("sl-SI"));
using (var ms = new MemoryStream())
{
using (var sw = new StreamWriter(stream: ms, encoding: new UTF8Encoding(true)))
{
    using (var cw = new CsvWriter(sw, cc))
    {
        cw.WriteRecords(ListOfReports);
    }// The stream gets flushed here.
    return File(ms.ToArray(), "text/csv", $"{docNumber.Trim()}_{docType}.csv");
}
}

It generated csv pretty nice, but the problem was, if I opened it in Excel, whole row was in the first column and was not splitted.

I added this part:

cw.WriteField("sep=,", false);
cw.NextRecord();

Before cw.WriteRecords(ListOfReports);, which made it work in Excel, but if I open it in Notepad, there is a sep=, in my first row.

I noticed there is a difference in CultureInfo, If I set "sl-SI" it will work properly on Slovenian windows (separator will be ;), if I set "en-US" it will work on English Windows (separator ,). But what do i need to do to work on any Culture?

Does anyone has any idea how to fix this so it will work properly in Excel and any other text editor?