Nintex Workflow – Regular Expression – Extract text from between two text strings

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Download the Workflow : Click here to download

Note: This workflow was built in Nintex Workflow 2.3.3.0.  If you are running an earlier build, it may not import.

Introduction

After using the Nintex Workflow Query LDAP action to retrieve some information, I ended up getting it in a distinguished name format:

CN=wombat,OU=Users,OU=US,OU=Support,DC=alphas,DC=vadimtabakman,DC=com

I needed to pull out the CN value.  It’s possible to do this with an Inline Function call like fn-SubString, but in order for that to work, you need to know exactly how long the substring is and it’s position in the input string.  Since the CN value can be any length, that would not work.

So the solution is to use a Regular Expression action, configured for an Extract.

The Regular Expression looks a little ugly, but it does what I need.

(?<=CN=)\w+(?=,)

If you have text that you need that has spaces in it, then try this:

(?<=CN=)[\w ]+(?=,)

If you are using Nintex Workflow Cloud, then the expression looks a little different, as NWC utilizes the Ruby Regular Expression syntax.

CN=([^,]*),

Explanation

(?<=CN=) – Positive lookbehind. Matches the “CN=” before your main expression without including it in the result.

\w+ – Matches 1 or more of any word character (alphanumeric & underscore)

(?=,) – Positive lookahead. Matches a “,” comma after your main expression without including it in the result.

This results in text between a CN= and a comma without include those bits of text.

Usage

This workflow is quite simple (3 actions).  So I won’t go into a great deal of detail.  The screenshots should suffice.

Workflow looks like this :

We will need 3 variables.

Collection variable : to store the results of the regular expression extract.

Number variable : to keep the index 0 as the first index into the collection variable

Text variable : to then get the first value from the collection and store it here.

Next we add the Regular Expression action.  I’ve typed in my input text, but if you use something like this, you’ll have the input text in a variable or item field.

The results are in a collection variable.  It’s possible with an Extract that you will get more than one result. eg. if instead of CN= you used DC=, you’d get 2 results.

Now we need to get the first result from the collection and store it in a text variable.

Finally, I want to update my Title field for my current item, with the CN value that I extracted.

That’s it.  It doesn’t really need more explanation than that.

This can be used to extract text from between any text strings, not just from a Distinguished Name.  Hopefully, this helps some people who has this requirement, as I’ve had in the past.

Conclusion

I always look for a way to make my workflows smaller.  Although a 3 action workflow is not exactly huge, when you start using this throughout a workflow, your workflow can grow quite quickly.

I had an idea to reduce this to 1 action.  This will be something I will write about in a future post.If I get it to work, I’ll post another article on it.  At this stage, I haven’t done this.

Downloads

Nintex Workflow 2013

Download the Workflow – Download and import it into the Workflow Designer Page

2 thoughts on “Nintex Workflow – Regular Expression – Extract text from between two text strings

  1. Wouter Terlunen says:

    Always appreciate your posts Vadim. Maybe a little off topic but as you refer to using regular expressions in nintex workflow cloud I wonder if you noticed that the replacement string is a mandatory field? So my problem is: how to eliminate spaces from a string? In NW365 I used pattern \s and an empty replacement string but what to do in NWC?

    1. Hey Wouter,
      That’s a good call out. So I have a workaround, but it’s not pretty 🙂
      Create 2 text Variables.
      textEmpty
      textSpace
      Add a Regular expression action first, and in the input, put in “a a” (without the quotation marks) and configure it to do a Replace. Pattern should be an “a” (no quotation marks) and Replacement Text should be your textEmpty variable. Store the result in textSpace.

      Now you’ll be able to do a replace with the “textSpace” variable in other Regex actions in your workflow.
      cheers,
      Vadim

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