Convert decimal to string without commas or dots

Question

In .NET, I need to convert a decimal amount (money) to a numbers-only string, i.e: 123,456.78 -> 12345678

I thought

var dotPos = amount.ToString().LastIndexOf('.');
var amountString = amount.ToString().Remove(dotPos);

would solve my problem, or at least part of it, but it didn't work as I expected. I'm trying to do this possibly without writing a lot of code and using something already designed for a similar purpose.

Answer 1

You could do it like this:

var amountString = string.Join("", amount.Where(char.IsDigit));

Using the char.IsDigit method will protect you from other unknown symbols like $ and will also work with other currency formats. The bottom line, you don't know exactly what that string will always look like so it's safer this way.

Answer 2

You say it's an amount, so I expect 2 digits after the decimal. What about:

 var amountstring = (amount * 100).ToString();

to get the cents-value without delimiters?

Or maybe even

var amountString = ((int)(amount * 100)).ToString();

to make sure no decimals remain.

EDIT
If a cast to int isn't quite what you want (It would just ignore any extra decimals, like Math.Floor), you can also use one of the Math.Round overloads, for instance:

var amountString = Math.Round(amount * 100, MidpointRounding.ToEven).ToString();

The MidpointRounding.ToEven (also known as "Banker's Rounding") will round a .5 value to the nearest even value, instead of always to the next higher value.

Answer 3

You don't need casts, you don't need to know where the decimal is, and you certainly don't need Linq. This is literally a textbook-case of Regular Expressions:

Regex regx = new Regex("[^0-9]");
var amountString = regx.Replace(amount, "");

Couldn't be simpler. And you can pass it strings with other odd monetary characters, or any character at all, and all you will get out is the decimal string.

Answer 4

var amountString = amount.ToString().Replace(".","").Replace(",","");