Use a custom thousand separator in C#

Luk picture Luk · Apr 15, 2009 · Viewed 38.2k times · Source

I'm trying not to use the ',' char as a thousand separator when displaying a string, but to use a space instead. I guess I need to define a custom culture, but I don't seem to get it right. Any pointers?

eg: display 1000000 as 1 000 000 instead of 1,000,000

(no, String.Replace() is not the solution I'd like to use :P)

Answer

Jon Skeet picture Jon Skeet · Apr 15, 2009

I suggest you find a NumberFormatInfo which most closely matches what you want (i.e. it's right apart from the thousands separator), call Clone() on it and then set the NumberGroupSeparator property. (If you're going to format the numbers using currency formats, you need to change CurrencyGroupSeparator instead/as well.) Use that as the format info for your calls to string.Format etc, and you should be fine. For example:

using System;
using System.Globalization;

class Test
{
    static void Main()
    {
        NumberFormatInfo nfi = (NumberFormatInfo)
            CultureInfo.InvariantCulture.NumberFormat.Clone();
        nfi.NumberGroupSeparator = " ";

        Console.WriteLine(12345.ToString("n", nfi)); // 12 345.00
    }
}