I have a string I need to split using a Regex. I could use the split methods in .NET but the string to return could be the first or second substrings. This regex will become a configurable setting in an application.
A typical string would be 9234567X123456-789
I've create the following regex
[-09]([^X]*)X
to return the first substring. However, I lose the first digit, 234567 is returned.
Any ideas?
Thanks.
Yes, you lose the first digit because it's being taken by the [-09] part. It's not clear why you've got that at all. I suspect you just want:
([^X]*)X
In other words, "capture everything before the first X, and check that there really is an X."
Sample code:
using System;
using System.Text.RegularExpressions;
public class Test
{
static void Main(string[] args)
{
Regex regex = new Regex("([^X]*)X");
string input = "9234567X123456-789";
Match match = regex.Match(input);
// TODO: Check for success
Console.WriteLine(match.Groups[1]); // 9234567
}
}
I'm assuming that you want the string to start with either -, 0 or 9. If this is true the regex you need (and using regexes here is overkill unless you want to also perform a sort of validation) is
([-09]\d*)X
OR
([-09][^X]*)X
if you are allowing any kind of character (not only digits) in the part before the X
EDIT:
Might have understood what you are looking for reading your sample string:
9234567X123456-789
You need either the first or the second group and every group can have digits or hypen (-). You solve this by creating two groups:
([\d\-]+)X([\d\-]+)
then you can check Jon Skeet's answer to get the data. You could either use
match.Groups[1]); //to get 9234567
or
match.Groups[2]); //to get 123456-789
