How to split a string based on every third character regardless of what the character is in c#

Question

Possible Duplicate:
.NET String.Format() to add commas in thousands place for a number

I am trying to add commas to a number for the presentation layer and need to cast and then split the number on every third character in order to join on a ','.

So if i have a string like this

546546555

desired output:

546,546,555

Other times, the number could be longer or shorter:

desired output:

254,654

Is it possible to split in this manner then join with a comma?

tahnks!

EDIT:

Hi Everyone,

Thanks very much for your help.

To add to this post I also found a way to do this in SQL:

SUBSTRING(CONVERT(varchar, CAST(NumItems AS money), 1), 0, LEN(CONVERT(varchar, CAST(NumDocs AS money), 1)) - 2) as [NumDocs]

Are you trying to do this...string.Format("{0:#,#}", 5465465555 ) — Gene S, Sep 24 '12 at 14:33
@JamesMichaelHare Hi James, it will always be an integer and never a decimal. — some_bloody_fool, Sep 24 '12 at 14:34
@GeneS Hi Gene, that looks solid, i will try that now, i am a novice programmer, didn't realize i had that formatt option — some_bloody_fool, Sep 24 '12 at 14:34
remember, the comma numeric group separator is a locale dependant character. in other parts of the world, the dot (.) aka period or point is used (and the comma is actually used as the decimal separator) — Les, Sep 24 '12 at 15:07

score 2 · Accepted Answer · answered Sep 24 '12 at 14:36

2

Rather than splitting the string manually, you should convert it to a number (or leave it as a number), and call the ToString method with the appropriate formatting:

Example

int value = 546546555;
string displayValue = value.ToString("#,#");

See this MSDN page for different format values:

C - Currency format

D - Decimal format

E - Scientific format

F - Fixed point format

G - General format

N - Number format

P - Percent format

R - Round trip format

X - Hexadecimal format

answered Sep 24 '12 at 14:36

Dan

9,717
4
47
65

Do you know of a way to mimick this logic in sql server 2008? – some_bloody_fool Sep 24 '12 at 17:03
That's a good question. I don't have an answer, but why not make it official and see what the community can come up with. – Dan Sep 24 '12 at 18:23

score 0 · Answer 2 · answered Sep 24 '12 at 14:36

You should do this by converting your string to an integer, using Parse or ideally TryParse and use string formatting to display it:

var str = "546546555";
var formatted = String.Empty;
int value = 0;
if(int.TryParse(str,out value))
{
   formatted = value.ToString("#,#");
}

Live example: http://rextester.com/FHO11833

score 0 · Answer 3 · answered Sep 24 '12 at 14:41

Assuming you aren't only trying to output numbers, here's a quick function that I believe would do what you are after:

string splitter(string tosplit, int num, string splitstring)
    {
        string output = "";
        for (int i = 0; i < tosplit.Length; i += num)
            if (i + num < tosplit.Length)
                output += tosplit.Substring(i, num) + ",";
            else
                output += tosplit.Substring(i);
        return output;
    }

Here, the output of splitter("546546555", 3, ",") would be 546,546,555

This would not be ideal for numbers though, as the other answers would cover this case perfectly.

score 0 · Answer 4 · answered Sep 24 '12 at 14:53

Not very good code, but it works.

public static string GetString(string val, int number)
        {
            List<string> res = new List<string>();
            res.Add("");

            int counter = 0, i = 0;
            while (i < val.Length)
            {
                while (res[counter].Length < number && i < val.Length)
                {
                    res[counter] += val[i];
                    i++;
                }
                res.Add("");
                counter++;
            }

            return string.Join(",", res.Where(r => !string.IsNullOrEmpty(r)));
        }

val - your input string number - number of characters you want to split, equals to 3 in your case

score 0 · Answer 5 · answered Sep 24 '12 at 15:05

Gene S and Dan seem to have the answer IMHO. The nice thing about using the built in formatting is that you can write localizable code. For example, the "," is the numeric group separator in the US, but the "." is used in Spain.

        var val = 12345678;
        CultureInfo c = CultureInfo.CurrentCulture;
        Application.CurrentCulture = new CultureInfo("EN-us");
        var s = String.Format("{0:#,#}", val);
        Application.CurrentCulture = new CultureInfo("ES-es");
        var i = String.Format("{0:#,#}", val);
        Application.CurrentCulture = c;

How to split a string based on every third character regardless of what the character is in c#

5 Answers5