Formatting strings into groups of 3 digits by periods

Question

I know I can format strings using the String.Format() method. Is it possible to format like this?

Example:

string: 1568
formatted: 1.568

string: 168794521
formatted: 168.794.521

string: 987
formatted: 987

Sorry that I can't make myself more clear.

Answer 1

You can format a number that way, but not a string. For example, if you have an integer value, you can use:

int value = 168794521;
string formatted = value.ToString("N0");

With the proper culture, this will format as shown.

If you are using a string, you would need to convert it. You could also explicitly provide a culture to guarantee "." as a thousands separator:

int value = Int32.Parse("168794521");
string formatted = value.ToString("N0", new CultureInfo("de-DE"));