Add decimal places to a decimal value

Question

I have an api that receive a decimal value as string.

e.g: "1.96"

I am parsing this string value with this code:

decimal.TryParse("1,96", out myDecimalVar)

But I need the following decimal value: 1.96000

How can I do it without Math.Round? Because Math.Round returns 1.97000

Tks!

That *is* the decimal value you have, are you trying to display this as a string somewhere? — Sayse, Feb 07 '17 at 14:10
If you want just an string format with N decimals, take a look here: http://stackoverflow.com/questions/3059759/double-tostring-with-n-number-of-decimal-places — Francesco Gusmeroli, Feb 07 '17 at 14:13
There is no way that Math.Round turns `1.96000` into `1.97000`. Your input is not what you think it is. — D Stanley, Feb 07 '17 at 14:38

Dmitry Bychenko · Accepted Answer · 2021-02-25T04:58:44.680

Unlike double and float, decimal is a BCD (Binary Decimal), so you can play a trick:

 // Be sure, that your current culture uses "," (comma)
 // as a decimal separator (e.g. Russian, ru-Ru culture)
 decimal.TryParse("1,96", out myDecimalVar);

 // add up a special form of zero
 myDecimalVar += 0.00000m;

 // 1,96000
 Console.Write(myDecimalVar);

for details, please, see

https://msdn.microsoft.com/en-us/library/system.decimal(v=vs.110).aspx

The binary representation of a Decimal value consists of a 1-bit sign, a 96-bit integer number, and a scaling factor used to divide the 96-bit integer and specify what portion of it is a decimal fraction. The scaling factor is implicitly the number 10, raised to an exponent ranging from 0 to 28.

So we have myDecimalVar being turned into 196000 integer number with -5 scale factor.

A more natural way, however, is to parse as it is, and represent as you want with a help of formatting:

 decimal.TryParse("1,96", out myDecimalVar);
 ...
 Console.Write(myDecimalVar.ToString("F5")); // 5 digits after the decimal point

score 0 · Answer 2 · answered Feb 07 '17 at 14:17

0

If you need it as a string then:

`       string v = "1.96";
        decimal d;
        decimal.TryParse(v, out d);
        Console.Write(d.ToString("f4"));
`

answered Feb 07 '17 at 14:17

afrose

169
1
9

Yeah, but I need a decimal output. thnks – Luis Antonio Pestana Feb 07 '17 at 15:37

score 0 · Answer 3 · answered Feb 07 '17 at 14:47

0

You have vary alternatives

decimal myDecimalVar;
decimal.TryParse("1,96", out myDecimalVar);
Console.WriteLine(myDecimalVar.ToString("0.00000")); // 1,96000
Console.WriteLine(myDecimalVar.ToString("F5"));      // 1,96000

as already answered.

answered Feb 07 '17 at 14:47

Marco Luongo

397
4
13

Yeah, but I need a decimal output. thnks – Luis Antonio Pestana Feb 07 '17 at 15:37

Add decimal places to a decimal value

3 Answers3