C# regular expression patterns

Question

I have a string like this:

String1=[q:6][ilvl:70](randomword)

and i need three patterns to retrieve the number 70 after the ilvl:, the number 6 after the q: and and one other pattern to retrieve all the ascii characters. I came up with these three patterns but i failed because they dont do excactly the three above.

string rules_1 = @"(?i)\[ilvl:([0-9]{1,2})\]";
string rules_2 = @"(?i)\[q:([0-9]{1,2})\]";
string rules_3 = @"(?i)\(([[:ascii:]+]+)\)";

The first one retrieves [ilvl:70] instead of 70 The second retrieves [q:6] instead of 6 and the third retrieves nothing instead of all ascii characters...

Any regular expression guru that can help me out here?!

Thank you in advance.

All are great solutions. Thank you everybody

user2530266
– user2530266

2014-06-25 14:09:58 +00:00
Commented Jun 25, 2014 at 14:09 — user2530266
– user2530266, Commented Jun 25, 2014 at 14:09

Grant Peters · Accepted Answer · 2014-06-25 02:26:55Z

Are you actually looking through the 'group' values of the match? The match will return EVERYTHING that matched, not just the things in "()" and group '0' will be everything as well.

This works as expected for me:

string String1="[q:6][ilvl:70](randomword)";

Regex rules_1 = new Regex(@"(?i)\[ilvl:([0-9]{1,2})\]");
Regex rules_2 = new Regex(@"(?i)\[q:([0-9]{1,2})\]");
Regex rules_3 = new Regex(@"(?i)\(([a-zA-Z]+)\)");

var match1 = rules_1.Match(String1);
var match2 = rules_2.Match(String1);
var match3 = rules_3.Match(String1);

var value1 = match1.Groups[1].Value;
var value2 = match2.Groups[1].Value;
var value3 = match3.Groups[1].Value;

Note that i had to change [[:ascii:]+]+ to [a-zA-Z]+ You can't nest the [] selectors (it doesn't make sense for one) and I've never seen :ascii:, but that would match ALL characters in this text anyway ([,:,0,7,etc. are also Ascii characters)

zx81 · Accepted Answer · 2014-06-25 02:08:19Z

Retrieve all three with a single regex:

^\[[^:]*:([^\]]*)\]\[[^:]*:([^\]]*)\]\(([^)]*)

In the demo, look at the capture groups in the right pane.

Sample code:

string s1 = @"[q:6][ilvl:70](randomword)";
Match matchResults = null;
var myRegex = new Regex(@"^\[[^:]*:([^\]]*)\]\[[^:]*:([^\]]*)\]\(([^)]*)");
matchResults = myRegex.Match(s1);
string firstNumber = matchResults.Groups[1].Value;
string secondNumber = matchResults.Groups[2].Value;
string yourASCII = matchResults.Groups[3].Value;

Explanation

The ^ anchor asserts that we are at the beginning of the string
\[[^:]*: matches everything up to the first :
([^\]]*) captures the first value to Group 1
\]\[[^:]*: matches everything up to the second :
([^\]]*) captures the second value to Group 2
\]\( matches up to the parentheses
([^)]*) captures your characters to Group 3

Grant Winney · Accepted Answer · 2014-06-25 02:10:57Z

1

You could just use string.Split:

var pieces = String1.Split(':', ']', '(', ')');

var qNumber = Convert.ToInt32(pieces[1]);    // 6
var lvlNumber = Convert.ToInt32(pieces[3]);  // 70
var rndWord = pieces[5];                     // randomword

I'm assuming you want any answer that will solve the problem for you.

Regex is powerful, but not always necessary.

answered Jun 25, 2014 at 2:10

Grant Winney

66.6k13 gold badges120 silver badges167 bronze badges

Comments

Avinash Raj · Accepted Answer · 2014-06-25 02:12:50Z

1

Your command needs a lookbehind to match all the three cases. You don't need to capture it.

(?:(?<=ilvl:)[^\]]*|(?<=q:)[^\]]*|(?<=\()[^\)]*)

DEMO

The below regex would store the matched characters into groups.

(?:(?<=ilvl:)([^\]]*)|(?<=q:)([^\]]*)|(?<=\()([^\)]*))

DEMO

Explanation:

(?:) Means a non capturing group.
(?<=ilvl:)[^\]]* matches the characters which are just after to ilvl: until a ] is detected.
| logical OR operator.
(?<=q:)[^\]] matches the characters which are just after to q: until a ] is detected.
| Logical OR operator.
(?<=\()[^\)]* matches the characters which are just after to ( until a ) is detected.

edited Jun 25, 2014 at 2:12

answered Jun 25, 2014 at 2:07

Avinash Raj

175k32 gold badges247 silver badges289 bronze badges

Comments

Hogan · Accepted Answer · 2014-06-25 02:42:18Z

1

Non-regex solution:

using System;

public class Program
{
  public static void Main()
  {
    string s1=@"[q:6][ilvl:70](randomword)";

    var tmp = s1.Split(new string [] {":","]" }, StringSplitOptions.None);

    string res1 = tmp[1];
    string res2 = tmp[3];

    string res3 = s1.Split(new string [] {"](",")" }, StringSplitOptions.None)[1];

    Console.WriteLine("1 -> "+res1);
    Console.WriteLine("2 -> "+res2);
    Console.WriteLine("3 -> "+res3);
  }
}

fiddle -> https://dotnetfiddle.net/84myVW

edited Jun 25, 2014 at 2:42

answered Jun 25, 2014 at 2:19

Hogan

70.7k10 gold badges83 silver badges119 bronze badges

Collectives™ on Stack Overflow

C# regular expression patterns

5 Answers 5

Comments

Comments

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

5 Answers 5

Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related