Have you ever wondered how you can edit the “currency appearance” in the .Net ToString() method? Let’s say we have var amount = 1337.42M; and we want it to be displayed like: 1'337.42 CHF.

Nothing easier than that you might think. Just write: amount.ToString("c"); and you are fine. But what is the output of our statement above (depending on your locale CultureInfo)? In my case it was: Fr. 1'337.42.

Changing the statement to amount.ToString("c", new CultureInfo("de-CH")); didn’t change anything.

After looking for the decimal.ToString() method in the MSDN docs, I found the right solution. I had to use the Decimal.ToString(String, IFormatProvider) method.

After using my custom NumberFormatInfo it was easy to display the number in the right format:

And the output was: 1'337.42 CHF.