次の方法で共有


Use of the Current() Function

One of the most annoying things that can happen in InfoPath is a problem that occurs when you are using Filtered Data to populate a second dropdown from the results picked in an initial dropdown in a repeating section or repeating table (a.k.a. cascading filtered dropdowns).  The problem can also arise in rules that set values of another field based on the selection of a dropdown value from inside a repeating table or repeating section.   The issue is that InfoPath doesn't know which node to refer to when you are in a repeating set of nodes, so it chooses the first set of values in the node.    This problem is particularly challenging because you don't see an issue until you add the 2nd node of a repeating section.   Often the users of your solution will find this before you do.  The trick here is that you need to delve a little into the underworld of XPath to get the right result.   Let's deal with the Filtered Data example first, because it's easier.   It's easy to set up the first dropdown values, that's a straightforward link to a secondary datasource.   The second set of dropdown values is simple to link in, but now you need to click on filtered data in order to give the query some criteria to limit the entries.   When you do it you'll end up with a line that looks like the first one below.   It is in the filter properties that we need to get fancy and use the current() function.  When you look at the filter, what you need to do is to click on Modify, and in the left-most drop down you need to select "The expression".   That will show you the XPath version of what you are actually doing.  You'll need to modify the line so that it looks like the After: entry.

Before: 

<../@somevaluefromsecondarydatasource=xdXDocument:get-DOM()/my:myFields/my:someothervalue>

After:

<../@somevaluefromsecondarydatasource=current()/my:someothervalue>

Now that doesn't look too hard, and it isn't, but sometimes it doesn't work.   I'm not an expert in traversing XML nodes using XPath, but I do now that the next thing to try when this fails is to change the line to read current()/../my:someothervalue.   I think this nomenclature is to force the code to start at the top of the XML node tree and then look down through, as opposed to starting where the current pointer in the node happens to be.  Don't quote me on that however because I've never been able to confirm that my inkling is correct.  This line will look more complex is the form you've built is based on a SQL or Access database.   You'll see stuff after the equals sign like xdXDocument:get-DOM()/dfs:myFields/dfs:dataFields/d:someothervalue, but all it's really doing is refererences a different schema related to the data connection you have with the database, so don't panic.

It gets trickier when you are setting up a rule that does a lookup and sets a value of another field.  Most typically you have a secondary datasource with at least two fields; the first field is used to populate a dropdown box in the repeating table/section, and the second field is populated by doing a lookup using filters where the value chosen in the dropdown equals a lookup value in the secondary datasource.   I'll assume that you can figure out how to build the filter using the standard GUI.   The trick will be now that the filter criteria is embedded in a longer line; typically the filter criteria is within brackets [ ].    You do the same procedure though, by changing what comes after the equals sign and putting either current()/ or curren()/../ in place of all the garbage that leads up to the actual nodename that you are filtering on (i.e. my:someothervalue).

All of this sounds complicated, and you can probably guess that I've struggled with it over time, which is why it belongs in my Blog.   If I'm too obtuse for you, you can try the other Blog entry that I've referenced below.

https://blogs.msdn.com/infopath/search.aspx?q=current()&p=1

Comments

  • Anonymous
    November 29, 2011
    Excellent info, thank you very much! I had spent hours reading many other blogs and posts but none of them showed the "Before" & "After" as you have. Also the need to include the "/../" when there are repeating sections or tables. Really big help!

  • Anonymous
    August 03, 2012
    Hi, thank you for sharing this technique. the URL which you referred at the end is not working. could you plz correct it. also, i tried by giving the expresstion as "ns2:Title=current()/../Field2InRepeatingTbl" could you plz help me. thank you

  • Anonymous
    October 10, 2012
    Could you update your last link? it is broken

  • Anonymous
    January 03, 2013
    Hi, I am newbie working on an Infopath form. I came across your blog while searching for a solution to an issue I am facing with repeating tables. I have a repeating table with the following columns: M1 M2 Lead Time There could be multiple rows with different values in each column. I am trying to evaluate the following formula when a button is clicked. The formula should be evaluated for each row in the repeating table. round((current()/group6/group7/M1 / 30.4) * current()/group6/group7/leadtime) + current()/group6/group7/M2 + current()/group6/group7/samples The issue is, the formula is evaluated for the first row and the result is repeated for all the subsequent rows. (i.e. the formula does not get evaluated for subsequent rows) any suggestion to fix this? Appreciate your help, Rohit

  • Anonymous
    October 15, 2013
    Spent the better part of a full day trying to figure this out. After many searches, I finally discovered the current() function, which eventually led me to your post. Problem solved! Thank you!

  • Anonymous
    November 03, 2013
    Thanks mate. Your blog was of much help to me!

  • Anonymous
    May 15, 2014
    THANK YOU!!!! you just saved a me a lot of headache!!!

  • Anonymous
    June 26, 2015
    I was having the "values in a repeating field set to first found" problem.  Your explanation of current() and especially the "current()/.." tip fixed this issue.  Thank you!