When creating a csv file, Excel shows double quotes

Question

I've created a .csv file using C# and when I open this file in Excel, it shows the double quotes in the cells.

When I open the csv in Notepad++ I see that are quotes are there and everything looks right to me. Here's a part of my csv:

"CertificaatNummer", "Data", "Inleg", "Getekend", "Ingangsdatum", "Betaalmethode", "Status", "Bonus", "Aankoopkoers", "Korting", "Garantiewaarde", "Betaalde termijnen", "Inleg nominaal", "Tweede naam", "Recht op bonus maand", "Begunstigde", "Product", "Incasserekening", "Uitbetaalrekening"
"126136", "some data with, a comma", "118.34", "True", "28-1-1999 00:00:00", "Cash", "C02", "0.00", "531,940", "0,000", "0.00", "0", "0.00", "", "False", "P.H. Bloemink", "Cash-Click", "", "260952095"
"137190", "other data", "0.00", "True", "23-12-1999 00:00:00", "Cash", "C02", "0.00", "660,620", "0,000", "0,00"

When I open this file in Excel it treats the comma in some data with, a comma as a new column. So I get "Some data with in one cell and a comma" in antother cell. As you see, Excel doesn't care about the double quotes.

Here's what my code looks like (simplified):

var content = new List<string>();

// Add headers
content.Add("\"Header 1\", \"Header 2\", \"Header 3\", \"Header 4\"");

// Add content
content.Add("\"123456\", \"some data with, a comma\", \"118.34\", \"True\"");
// etc..

// I let a function create my file content
using (var stream = new MemoryStream())
using (var writer = new StreamWriter(stream))
{
    foreach (var line in this.content)
    {
        writer.WriteLine(line);
    }

    writer.Flush();
    return stream.ToArray();
}

// finally I return the file content to the browser with 
// HttpContext.Response.AddHeader("content-disposition", "file;name=" + fileName);

The question is, which part of my code do I have to edit so Excel will display my file properly? I rather want to edit my code then executing some tricks in Excel.

Answer 1

The problem seems to be spaces after the comma separators.
Instead of

"some, text","Other text"

your code is generating:

"some, text",<space>"Other text"

So the Excel CSV importer is getting flummoxed. Remove those extra spaces and you should be OK.

Answer 2

Some time ago, I found out that Excel likes its CSV files UTF-16LE encoded, with tabs (ASCII code 9) as delimiters. It even accepts (and removes) double quotes around the values.