NSXMLElement with solo tag . ie.

Question

I'm trying to create a XML string which should contain solo tags (ie. tag without separate closing tags) I am able to create normal xml tags like

<tagname attribute=attributevalue></tagname>

using the code

NSXMLElement *childElement=[[NSXMLElement alloc] initWithName:childName];
childElement.stringValue=childValue;
[childElement addAttribute:[NSXMLNode attributeWithName:attributeName stringValue:attributeValue]];
[self.currentNode addChild:[childElement copy]];

but I need it like this

<tagname attributename=attributevalue />

score 8 · Answer 1 · answered Sep 07 '12 at 07:27

Before saving your file, when creating NSData, add this option : NSXMLNodeCompactEmptyElement

Like this :

NSData *xmlData =
  [xmlDoc XMLDataWithOptions:NSXMLNodePrettyPrint | NSXMLNodeCompactEmptyElement];

Then serialize your file :

  [xmlData writeToURL:theFile atomically:YES]

Reference : NSXMLNode class reference
Section Constants

NSXMLNodeExpandEmptyElement
  Requests that an element should be expanded when empty; for example, <flag></flag>. This is the default.
  Available in Mac OS X v10.4 and later. Declared in NSXMLNodeOptions.h.

NSXMLNodeCompactEmptyElement
  Requests that an element should be contracted when empty; for example, <flag/>.
  Available in Mac OS X v10.4 and later. Declared in NSXMLNodeOptions.h.

score 2 · Answer 2 · answered Apr 20 '12 at 10:16

2

<tagname attribute=attributevalue></tagname>

and

<tagname attributename=attributevalue />

are completely equivalent in XML and it is only a question of formatting how do you write them. If you don't have some particular reason to create "beautifully formatted" XML source code, I wouldn't bother myself with it.

Also, the code above does not create neither representation: it stores the data in an internal structure not if the form of XML source code. Your question might be valid only when you want to export the XML tree structure into a XML source file.

answered Apr 20 '12 at 10:16

MrTJ

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The server that I want to communicate with is ASP. Does XML parser in ASP consider both of them the same? – Renjith Apr 20 '12 at 10:19
I don't know the XML parsers under ASP but I if it does not accept both formats then it is a very serious bug in the parser since both are standard (and equivalent) XML segments. – MrTJ Apr 20 '12 at 12:41
1

But to be sure, let's go back to the XML specification: http://www.w3.org/TR/REC-xml/#d0e2433 `An element with no content is said to be empty. The representation of an empty element is either a start-tag immediately followed by an end-tag, or an empty-element tag.` AND `Empty-element tags may be used for any element which has no content, whether or not it is declared using the keyword EMPTY. For interoperability, the empty-element tag SHOULD be used, and SHOULD only be used, for elements which are declared EMPTY.` Note: `SHOULD` is not obligatory, so you're still good if you use the other form – MrTJ Apr 20 '12 at 12:46

score 1 · Answer 3 · answered Apr 20 '12 at 13:08

Everything MrTJ says is correct, but it's possible that the serializer is being confused because you have set the text content of the node. It may be that it sees the text content node (even though it has a zero length string) and creates start and end tags because it exists at all.

Try something like:

if ([childValue length] > 0)
{
    childElement.stringValue=childValue;
}

NSXMLElement with solo tag . ie.

3 Answers3