See if this helps?

https://community.nintex.com/message/56726-re-add-variable-to-url-on-nintex-form?commentID=56726#comment-56726 

Hi ‌, thanks for the suggestion (do you ever sleep? you answer question all the time! ) but I don't think it's applicable to my scenario..

I'm using the standard hyperlink control because I have to show the link that is set in that specific column (with URL and description, so it should show the description and link to the URL) and that column is updated by a workflow..

Haha why sleep when you can be on the community! No just kidding. Only jumped in with that as I was so amazed by what ‌ posted on that thread I need to share it (and thought it might help)! 

do you have control over what link is written to the list field in workflow?

if so, you could inject 'target' attribute into link there.

not for what I know..SharePoint hyperlink field is composed by two subfields, one for URL and one for description..no place on how it's rendered..

OK.

so, I haven't realized first it's sharepoint hyperlink field. you are right, this filed doesn't allow to customize link attributes OOTB .

my other idea was a link in a form 'javascript:window.open('URL');' might be a way to go (which is by specification valid href entry).

but unfortunately after some tests I found out, that sharepoint tries to be super-intelligent and changes provided URL string to something what it thinks the URL should look like. so it eg. prepends protocol specifier (http://, file:// ...) or site URL, etc.

all that (quite significantly) restricts usability of hyperlink-type field.

so if you are stick to use hyperlink-type field, you will likely need to customize link's attributes at client side (javascript).

if you still have chance to change field's datatype, I would suggest to make it numeric field and build whole link definition (html element)  on your own.

with such a setup and Oldest SharePoint trick ever () described by Ryan Greenaway‌ you could IMHO achieve the same functionality.

Hi all,

I faced similar need with link inside a label for a "I agree terms and conditions" checkbox.

My work around was using javascript as following:

1° add a css class name to my label (ex: lblLink)

2° in form setting / custom javascript, add the following javascript:

I realize this is an older post, but I stumbled across it while trying to do the same thing so, I thought I'd add my two cents.

I didn't want to apply this rule to all <a> tags, but I did want to add it to all hyperlink fields on the form. 

As you've all discovered, it seems custom CSS classes and JavaScript variables set in the form controls don't get set when the form is in display mode (which is very unfortunate).

I decided to look for some other unique-ish identifier, and came across the 

data-formcontroltypeid="a0c89d70-0781-4bd4-8623-a73675005a05"‍

Now, I have no idea if this is the same for everyone else out there (please comment if it is or isn't), but it is the same for me even across different site collections. So, I felt this would work well for me.

I then used this line of code and it's working perfectly:

NWF$("div"data-formcontroltypeid='a0c89d70-0781-4bd4-8623-a73675005a05'] a").prop('target','_blank');‍

The code finds all <div> objects with that specific 'data-formcontroltypeid'.

Then it finds all <a> objects inside the <div> objects.

Lastly, it applies the target property set to '_blank' to the <a> object.

And actually, in my case, I took it a step further since I know this will only be needed when in Display Mode:

var isDisplayMode = document.location.pathname.indexOf("/DispForm.aspx") > -1;
if (isDisplayMode) NWF$("divndata-formcontroltypeid='a0c89d70-0781-4bd4-8623-a73675005a05'] a").prop('target','_blank');
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