Custom Thousand Separator In C#

I guess the NFA requires us to use a space (" ") instead of a comma (",") as our thousands separator. I dunno why the have to regulate something like that, but I had to figure out an elegant way to format our numbers the way the powers that be require them to be formatted.

After struggling with different inelegant solutions for a little while, I finally realized that different countries use different symbols as thousands separators; I knew then that my problem was really a localization problem. A quick search in MSDN lead me to the NumberFormatInfo class, which "defines how numeric values are formatted and displayed, depending on the culture" (MSDN).

The NumberFormatInfo class, has a NumberGroupSeparator property that defines what character to use to separate thousands.

So, here's how I ended up solving my problem:

public void FormatDouble(double doubleToFormat)
{
     NumberFormatInfo nfi = new CultureInfo("en-US", false).NumberFormat;
     nfi.NumberGroupSeparator = " ";
     Write(doubleToFormat.ToString("n", nfi);
}

Neat, huh?