Remove Empty XML Tags

Hi Guys,

I am looking for a way to remove empty XML tags.

Example.

if the follow do not contain strings/data
<number>#</number>
<expiry>#</expiry>

is it possible to remove the entire tag?

Regards,
Fraser

Did you try node.remove()? Check the online Help for complete description and code snippet.

You can probably write a little helper function which can iterate through all the XML nodes the tree using nodeType() and :nodeValue() and strip out all the empty tags like this.

Thanks for the replies guys.

I’m unable to select the tags i want to remove if they have duplicate names.

Example:
<recipient>
<identifiers>
<identifier>
<number></identifier>
</identifier>
<identifier>
<number></identifier>
</identifier>
</identifiers>
</recipient>

I am wanting to remove the second identifier.
If i use the following: recipient.identifiers:remove(‘identifier’) it works fine.
When i use: recipient:child(“identifiers”):remove(“identifier”, 2) i received “2 arguments expected, got 3”.

I have tried using other methods but can’t seem to figure out a way to remove the second duplicate fields.

Thanks for your help

What you’ve provided isn’t valid XML, frazcat, and I’m not quite sure what you’re looking for. Is this more representative of what you’re dealing with?
[code]
<recipient>
<identifiers>
<identifier>1234</identifier>
<identifier></identifier>
<identifier>3456</identifier>
<identifier></identifier>
</identifiers>
</recipient>
[/code]
I’ve written a little node method that would turn the above into:
[code]
<recipient>
<identifiers>
<identifier>1234</identifier>
<identifier>3456</identifier>
</identifiers>
</recipient>
[/code]
Is that what you need?

Jeff Drumm ◊ VP and COO ◊ HICG, LLC. ◊ http://www.hicgrp.com

I’ve re-read your request and think I’ve figured out what you’re trying to do. The code below will remove only the 2nd child of <recipient> named <identifier>.

local X  = xml.parse{data=Data}
local Y  = X.recipient:child('identifiers')
local id = Y:childCount('identifier')
for i=Y:childCount(),1,-1 do
   if Y[i]:nodeName() == 'identifier' then
      if id == 2 then
         Y:remove(i)
      else
         id = id - 1
      end
   end
end

Jeff Drumm ◊ VP and COO ◊ HICG, LLC. ◊ http://www.hicgrp.com

G’day frazcat,
I don’t know if this is any use to you but it might give you some ideas. Its some code that I used when building a FHIR interface in Iguana. Essentially, it iterates through an XML node tree and removes any empty nodes. It looks for data in both content and attributes.

--++++++++++++++++++++++++++++++++++++++++++++++++++
-- Iterate through a node and delete any empty child nodes
function node:fhirDropEmpty()
   for nChild = self:childCount(), 1 , -1 do
      if self[nChild]:fhirIsEmpty() then
         self:remove(nChild)
      elseif self[nChild]:nodeName() == 'div' then
      else
         self[nChild]:fhirDropEmpty()
      end
   end 
   return self
end
h = {}
h.Title = 'node:fhirDropEmpty'
h.Desc = 'Iterates through the node tree and removes any empty nodes'
h.Usage = 'node:fhirDropEmpty()'
h.Returns = {}
h.Returns[1] = {}
h.Returns[1].Desc = 'Node: a Reference to the node'
help.set{input_function=node.fhirDropEmpty, help_data=h}

--++++++++++++++++++++++++++++++++++++++++++++++++++
-- Determines if a node does not contain any data
function node:fhirIsEmpty()
   local bIsEmpty = true

   if self:isLeaf() and self:nodeValue() ~= '' then
      bIsEmpty = false
   elseif self:nodeName() == 'div' and self:childCount() > 0 then
      bIsEmpty = false
   else      
      for n=1, self:childCount() do
         if self:childCount() == 1 and self[1]:nodeName() == 'xmlns' then
         elseif self:childCount() == 1 and self[1]:nodeName() == 'value' and self[1]:nodeValue() ~= '' then
            bIsEmpty = false
            break
         elseif not self[n]:fhirIsEmpty() then
            bIsEmpty = false
            break         
         end
      end
   end
   
   return bIsEmpty
end
h = {}
h.Title = 'node:fhirIsEmpty'
h.Desc = 'Determines if the node or any of the child nodes contains any valid values'
h.Usage = 'node:fhirIsEmpty()'
h.Returns = {}
h.Returns[1] = {}
h.Returns[1].Desc = 'Boolean: True if the node or child nodes contains no values, False if values found'
help.set{input_function=node.fhirIsEmpty, help_data=h}

Thanks, Garry. That code saved me hours!

My pleasure Brett. I’m glad it helped.