InfoPath how to copy a repeating section using rules

For years, we all thought this was impossible.  You had to use code.  I somehow woke up with an idea on how to do this, and set about testing and to my surprise, found a solution.  Here it is!

The form set up

• Two repeating sections, Foo's and Bar's
• One additional integer field i to control which row to copy

Put the elements on the form:

The copy rule

Create a rule on the integer field i

1. We will use the normal action, then tweak it. 
   Give this rule the name "Copy"
   Start by defining a set field value rule.
   
   
2. Set /my:myFields/my:Foos/my:Foo/my:F1 to /my:myFields/my:Bars/my:Bar/my:B1
   
   
   There are a few issues so far with the default Set Field Value action related to a repeating section.
• For the Field (target), it will set ALL the matching nodes.
• For the Value, it will get the First matching node.
  
3. Let's fix the second value - we can do this in InfoPath designer.
   
   
   The expression is:
   ../my:Bars/my:Bar[number(../../my:i)]/my:B1
   
   This expression lets us copy a different row.
   
   
   
   So we can now copy value from any row - depending on what the number i is.
   
4. To fix the Field Target is a bit more difficult.  InfoPath designer doesn't give us a way to modify the XPath of the field.
   
   
5. Save the form.  We're about to do unsupported stuff. 
6. Publish the form to Source Files. 
   
   
   I publish to C:\Temp\CopyForm\
   
7. Close InfoPath designer.  Open the file C:\Temp\CopyForm\manifest.xsf file using NotePad or your favourite XML editor.
   
8. The "Copy" rule is hiding in this XML file, it looks like this:
   

<xsf:rule caption="Copy">
    <xsf:assignmentAction targetField="../my:Foos/my:Foo/my:F1" expression="../my:Bars/my:Bar[number(../../my:i)]/my:B1"></xsf:assignmentAction>
</xsf:rule>

9. Change it to:
   
<xsf:rule caption="Copy">
<xsf:assignmentAction targetField="../my:Foos/my:Foo[number(../../my:i)]/my:F1" expression="../my:Bars/my:Bar[number(../../my:i)]/my:B1"></xsf:assignmentAction>
</xsf:rule>
10. Save, and close Notepad.  Re-open manifest.xsf file using InfoPath Designer
    
11. Let's check our rule.
    
    
12. Are you thinking what I'm thinking?  We're nearly there.

The loop

1. This rule is set on the number i, and runs once whenever the number i changes.
   
2. Lets set it up to increment.
   
   
3. Add a condition to stop incrementing when we've run out of rows
   
   
   
   
4. And to start the whole thing, remember we have a button.
   
   
   
   To start the process, set i to 1.  XML index starts from 1 to n.  Does not start at 0.
   

Result - InfoPath Filler

Starting...

Press "Copy"

Result - Form Server:

Starting Browser Form

Copy.

Note - InfoPath "Infinite Loop" limitation:

InfoPath is hard coded to only execute 16 rules before throwing the "Infinite Loop" error.



An error occurred in the form's rules or code. The number of rule actions or the number of calls to the OnAfterChange event for a single update in the data exceeded the maximum limit.

The rules or code may be causing an infinite loop. To prevent this, ensure that the rule action or event handler does not update the data which causes the same rule action or event handler to execute.

There is no solution for hard coded 16 rules.  So your i can not go over 16.

Download

• http://johnliu.net/storage/CopyForm.xsn

Comments

[Gareth]

Hi I'm a relative noob with InfoPath so please excuse any dumbness here but...

... Am I right in thinking this won't work in browser based form due to lack of support for referencing repeating sections by index number?

Some great info here btw, thanks.

[JohnLiu.NET]

This works fine in browser forms :-)
See my screen shots above under Result- Form Server

[Steve]

This is a great post!

I used this concept to solve a problem that I had and it worked great. I didn't need to edit manifest.xsf because what I was doing was executing a rule (a data connection query) for each row of a repeating table, so my 'set a fields value' target was always the same field. But I did have a bit of trouble specifying the index field in the square brackets ... when I picked the field it put a dot in there, and it would not work. I replaced it with the full relative xpath (../../group/group/field) and it worked.

Thanks much for posting this.

[Scott T.]

This is very cool and works very well when both repeating tables have the same number of rows, but how do you add addtional rows to the target table if it doesn't have as many rows?

[JohnLiu.NET]

Bad news Scott,

We can't add new rows without using code.
Try adding more default rows in your target repeating section?

[Ken G]

I feel like i'm close, but I can't get i to increment. I'm using InfoPath 2007. Will this work in InfoPath 2007? Also, I'm trying to trigger the loop when the form opens, by adding a rule on the Form --> Options screen. Do you see any reason why triggering the increment will not work from this entry point?