I need help with string.format to insert three spaces every three digit. This digit is at a fixed length at 12 digits.
var membershipNo = string.Format("{0:### ### ### ###}", "123123123123");
Console.WriteLine(membershipNo);
Result: 123123123123
Expected: 123 123 123 123
0:### ### ### ###is a numeric format string, not a string format. Where are the digits inmembershipNocoming from? If they're always digits why are you storing them as a string not an long?"000123123123"?