Extracting values using Regex - C#

Question

I'm not much familiar with Regular expressions. I've a string from which I need to extract specific values using regex. Here is the string

CN=ReportingGroup {b4f3d644-9361-461e-b604-709fa31f2b9e},OU=DOM USERS,DC=domain,DC=com

I want to get the values of CN and OU namely "ReportingGroup {b4f3d644-9361-461e-b604-709fa31f2b9e}" and "DOM USERS "

from the above string. How can i construct the regex pattern for that?

Oded · Accepted Answer · 2010-12-16 13:43:33Z

7

You don't need a RegEx for this.

If you split the string using , and then each resulting string with =, you can look through the keys in order to extract the value for the CN and the OU keys.

string cn;
string ou;
foreach(string adPortion in myString.Split(new Char [] {','}))
{
   string[] kvp = adPortion.Split(new Char [] {'='})

   if(kvp[0] == "CN")
      cn = kvp[1];

   if(kvp[0] == "OU")
      ou = kvp[1];
}

This assumes that CN and OU only appear once in the string.

answered Dec 16, 2010 at 13:43

Oded

501k102 gold badges900 silver badges1k bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Mr. TA Over a year ago

I would advise against going this route. By performing manual splits, you would be effectively doing what Regex will do for you behind the scenes.

Oded Over a year ago

@Mr. TA - can you please expand on why a RegEx would be preferable?

Mr. TA Over a year ago

Oded - Regexes were made specifically for the purpose of parsing strings. Your solution involves 12 lines of code, whereas with Regex, the whole thing fits into a one-liner. But line count aside, there's no reason at all to re-invent the wheel. Additionally, it's a good exercise for a beginner developer to learn Regex now that they have this relatively simple task to solve.

A_Var Over a year ago

I would disagree with TA. Regex sometimes are an overkill for the application. IF you understand behind the scenes of regex (initializing a parser,scanner for tokens, building the parse tree etc....). But simple code like Oded will make it fast and makes much more sense.

Mark Cooper Over a year ago

I agree with @Oded here. Whilst the OP wanted a RegEx the provided solution is a perfectly acceptable alternative and easier to understand and therefore cheaper to maintain. When considering whether to use RegEx always remember the ancient proverb; "I used regular exressions to solve a problem. Now I have two problems."

Mr. TA · Accepted Answer · 2010-12-16 13:43:56Z

5

Do the following:

new Regex("CN=(?<CN>[^,]*),OU=(?<OU>[^,]*)").Match(str).Groups["CN"].Value;

answered Dec 16, 2010 at 13:43

Mr. TA

5,3771 gold badge31 silver badges37 bronze badges

2 Comments

Liviu Mandras Over a year ago

@ NLV See what I mean?, If you are not a Regex expert it is plain Chinese to non-chinese people :)

A_Var Over a year ago

this is good too but won't agree it's faster than oded's solution.

Liviu Mandras · Accepted Answer · 2010-12-16 13:45:09Z

1

It looks like your string is pretty well structured. Consider using regular string functions like IndexOf() and Substring(). Regex are harder to read and understand.

answered Dec 16, 2010 at 13:45

Liviu Mandras

6,6272 gold badges45 silver badges68 bronze badges

Comments

Sam B · Accepted Answer · 2010-12-16 13:48:03Z

0

If you absolutely want to use Regex, the following code will iterate though all KEY=VALUE pairs:

        foreach (Match m in
            Regex.Matches(inputString, @"[,]*([^=]+)=([^,]*)"))
        {
            string key = m.Groups[1].Value;
            string value = m.Groups[2].Value;
        }

answered Dec 16, 2010 at 13:48

Sam B

2,4812 gold badges18 silver badges20 bronze badges

Collectives™ on Stack Overflow

Extracting values using Regex - C#

4 Answers 4

5 Comments

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

5 Comments

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related