How to get the Index of second comma in a string

Question

I have a string in an Array that contains two commas as well as tabs and white spaces. I'm trying to cut two words in that string, both of them before the commas, I really don't care about the tabs and white spaces.

My String looks similar to this:

String s = "Address1       Chicago,  IL       Address2     Detroit, MI"

I get the index of the first comma

int x = s.IndexOf(',');

And from there, I cut the string before the index of the first comma.

firstCity = s.Substring(x-10, x).Trim() //trim white spaces before the letter C;

So, how do I get the index of the second comma so I can get my second string?

I really appreciate your help!

why don't you `split(',')` and then get all slices in one array? — balexandre, Mar 26 '14 at 17:47
@shree.pat18 Good question. Sometimes it does and sometimes it does not have 2 commas. — Sem0, Mar 26 '14 at 17:47
[Get index of nth occurrence of char in a string](http://stackoverflow.com/questions/11363083/get-index-of-nth-occurrence-of-char-in-a-string) — huMpty duMpty, Mar 26 '14 at 17:48
`s.Split(',').Skip(1).First()` could have done the job. No need to find indexes of characters. — Jatin Sanghvi, Jun 29 '18 at 18:53

score 115 · Accepted Answer · answered Mar 26 '14 at 17:52

115

You have to use code like this.

int index = s.IndexOf(',', s.IndexOf(',') + 1);

You may need to make sure you do not go outside the bounds of the string though. I will leave that part up to you.

answered Mar 26 '14 at 17:52

Logan Murphy

6,120
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BenVlodgi · Answer 2 · 2021-07-09T14:12:46.810

I just wrote this Extension method, so you can get the nth index of any sub-string in a string.

Note: To get the index of the first instance, use nth = 0.

public static class Extensions
{
    public static int IndexOfNth(this string str, string value, int nth = 0)
    {
        if (nth < 0)
            throw new ArgumentException("Can not find a negative index of substring in string. Must start with 0");
        
        int offset = str.IndexOf(value);
        for (int i = 0; i < nth; i++)
        {
            if (offset == -1) return -1;
            offset = str.IndexOf(value, offset + 1);
        }
        
        return offset;
    }
}

BlyZe · Answer 3 · 2022-05-31T11:14:27.010

-1

LastIndexOf gives you the Index of the last occurence of the given char / string.

int index = s.LastIndexOf(',');

edited May 31 '22 at 11:14

answered May 25 '22 at 20:52

BlyZe

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1
10

Kindly add more details to your answer, explanations on how your code works and how this address the OP's question would be a great help not just for the asker but also for the future researchers. – Kuro Neko May 31 '22 at 05:49
this is not the second but the last – Paramar Jun 15 '22 at 14:54

How to get the Index of second comma in a string

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