C# equivalent of BigDecimal.stripTrailingZeros()

Question

In Java you can use BigDecimal.stripTrailingZeros() to remove any extra zeros at the end.

I've read a few questions on here about how to strip trailing zeros from a decimal in C# but none of them seem to offer correct solutions.

This question for example the answer of doing ToString("G") doesn't always work.

Ideally I would like a function that does decimal -> decimal with the new decimal having the least scale possible without losing any info or removing any trailing zeros.

Is there any way to do this easily? Or would it involve fiddling around with decimal.GetBits()?

EDIT: Should also add I have i18n to worry about so doing string manipulation on the result isn't ideal because of differences in decimal separators.

well the answer that mentions trimming seems more effective and should work in all cases.. use that http://stackoverflow.com/questions/4525854/remove-trailing-zeroes/4525896#4525896 — Shekhar_Pro, Feb 21 '11 at 14:43
Check out Marc Gravell's answer in this post: http://stackoverflow.com/questions/2714645/decimal-truncate-trailing-zeros. It does decimal to decimal just as you asked. — Doctor Jones, Feb 21 '11 at 14:51
@Shekhar: Actually, the answers in that question using trimming are badly broken. — Ben Voigt, Feb 21 '11 at 15:02
@DoctaJonez - Unfortunately that answer doesn't strip the zeros. I have ToString() -> 1000.0000 beforehand and ToString() -> 1000.0000 afterwards. — Mike Q, Feb 21 '11 at 15:17

score 2 · Answer 1 · answered Feb 21 '11 at 16:05

2

How about Decimal.Parse(d.ToString("0.###########################"))?

answered Feb 21 '11 at 16:05

Gabe

84,912
12
139
238

it dosent work.. `decimal.Parse(1000.001M.ToString("0.#"))` gives `1000` we loose the `001` after decimal – Shekhar_Pro Feb 21 '11 at 16:12
Again it fails for `1000.000000000000000000000000000100M` ha ha expand it up to the maximum digits avail :D – Shekhar_Pro Feb 21 '11 at 16:19
ok your answer works.. my extra digits are being actually truncated – Shekhar_Pro Feb 21 '11 at 16:20
+1 I tested your code with my samples and it works..+1 for the simplest answer here.. – Shekhar_Pro Feb 21 '11 at 16:25

Shekhar_Pro · Accepted Answer · 2011-02-21T16:22:40.990

Here is what i have come up with (Crazy code but works smoothly)

private decimal Normalize(decimal d)
{
    string[] tmp = d.ToString().Split('.');
    string val = tmp[0];    
    string fraction = null;
    decimal result;
    if(tmp.Length > 1) fraction = tmp[1];
    if(fraction != null && Getleast(fraction) > 0) 
    {
        decimal.TryParse(val.ToString() + "." + fraction.TrimEnd('0').ToString(),out result);
    }
    else
    {
        return decimal.Parse(val);
    }
    return result;
}

private decimal Getleast(string str)
{
    decimal res;
    decimal.TryParse(str.TrimEnd('0'),out res);// It returns 0 even if we pass null or empty string
    return res;
}

Here are sample Input:

Console.WriteLine(Normalize(0.00M));
Console.WriteLine(Normalize(0.10M));
Console.WriteLine(Normalize(0001.00M));
Console.WriteLine(Normalize(1000.01M));
Console.WriteLine(Normalize(1.00001230M));
Console.WriteLine(Normalize(0031.200M));        
Console.WriteLine(Normalize(0.0004000M));
Console.WriteLine(Normalize(123));

And respective output:

Not quite so simple, you need to check for the presence of a decimal point first. Otherwise you end up with ridiculous results like http://ideone.com/DXokE — Ben Voigt, Feb 21 '11 at 14:58
yeah i am working on my LINQPAD to get somthing working with strings... till then maybe marks answer is good — Shekhar_Pro, Feb 21 '11 at 15:07

BenE · Answer 3 · 2011-02-21T19:59:48.503

0

Not the most elegant of solutions but it should do everything you need.

 private decimal RemoveTrailingZeros(decimal Dec)
    {
        string decString = Dec.ToString();

        if (decString.Contains("."))
        {
            string[] decHalves = decString.Split('.');

            int placeholder = 0, LoopIndex = 0;

            foreach (char chr in decHalves[1])
            {
                LoopIndex++;
                if (chr != '0')
                    placeholder = LoopIndex;
            }

            if (placeholder < decHalves[1].Length)
                decHalves[1] = decHalves[1].Remove(placeholder);

            Dec = decimal.Parse(decHalves[0] + "." + decHalves[1]);
        }

        return Dec;
    }

Fixed version, Thanks Shekhar_Pro!

edited Feb 21 '11 at 19:59

answered Feb 21 '11 at 16:00

BenE

67
5

it failed for `RemoveTrailingZeros(1000.01M)` at line `decHalves[1] = decHalves[1].Remove(placeholder);``ArgumentOutOfRangeException` Exception – Shekhar_Pro Feb 21 '11 at 16:16
in decimal we don't have any i18n issues.. it comes when we convert it to string.. you can always have culture neutral string conversion for this particular processing... – Shekhar_Pro Feb 21 '11 at 16:27

C# equivalent of BigDecimal.stripTrailingZeros()

3 Answers3