Regexp find position of different characters in string

Question

I have a string conforming to the following pattern:

(cc)-(nr).(nr)M(nr)(cc)whitespace(nr)

where cc is artbitrary number of letter characters, nr is arbitrary number of numerical characters, and M is is the actual letter M.

For example:

ASF-1.15M437979CA 100000
EU-12.15M121515PO 1145

I need to find the positions of -, . and M whithin the string. The problem is, the leading characters and the ending characters can contain the letter M as well, but I need only the one in the middle.

As an alternative, the subtraction of the first characters (until -) and the first two numbers (as in (nr).(nr)M...) would be enough.

Since (cc) and (nr) cannot contain a '-' or '.' why don't you use [IndexOf](https://msdn.microsoft.com/en-us/library/k8b1470s%28v=vs.110%29.aspx)? After finding the '.' You can search for the 'M' in a position after '.'. — Mehrzad Chehraz, May 18 '15 at 11:56
Can you edit your question and add the solution you have so far? Thanks! — Luís Cruz, May 18 '15 at 11:56
I have the solution, Mehrzad Chehraz is providing. But i want to have a nice one:-) — Freud, May 18 '15 at 11:58
Include your solution then and we'll make it nicer if needed to be. — Mehrzad Chehraz, May 18 '15 at 11:59

Wiktor Stribiżew · Accepted Answer · 2015-05-18T12:20:36.350

If you need a regex-based solution, you just need to use 3 capturing groups around the required patterns, and then access the Groups[n].Index property:

var rxt = new Regex(@"\p{L}*(-)\d+(\.)\d+(M)\d+\p{L}*\s*\d+");
// Collect matches
var matches = rxt.Matches(@"ASF-1.15M437979CA 100000  or  EU-12.15M121515PO 1145");
// Now, we can get the indices
var posOfHyphen = matches.Cast<Match>().Select(p => p.Groups[1].Index);
var posOfDot = matches.Cast<Match>().Select(p => p.Groups[2].Index);
var posOfM = matches.Cast<Match>().Select(p => p.Groups[3].Index);

Output:

posOfHyphen => [3, 32]
posOfDot    => [5, 35]
posOfM      => [8, 38]

score 0 · Answer 2 · answered May 18 '15 at 12:05

Regex:

string pattern = @"[A-Z]+(-)\d+(\.)\d+(M)\d+[A-Z]+";
string value = "ASF-1.15M437979CA 100000  or  EU-12.15M121515PO 1145";

var match = Regex.Match(value, pattern);

if (match.Success)
{
    int sep1 = match.Groups[1].Index;
    int sep2 = match.Groups[2].Index;
    int sep3 = match.Groups[3].Index;
}

Regexp find position of different characters in string

2 Answers2