ARTICLE
iXML Library - DOM Writes
Writes enable an XML document to be constructed from scratch in
the memory or an existing document to be modified. The most important
methods used to construct a DOM create elements and add
attributes to elements. These methods are declared in the interface
IF_IXML_DOCUMENT are summarized
here. Other methods are used to remove elements from a DOM , which
is described in the interface documentation (see also
Rendering Examples ).
Notes
Writes to the DOM must be avoided during
sequential parsing , since this can
produce unexpected behavior.
iXML documents can also be specified as an XML target for
XSL transformations called using
CALL TRANSFORMATION .
If writes produce content of elements or attributes, the characters
, , , " , and ' are
transformed automatically into the associated XML
notation .
Adding Nodes
Nodes are usually added to existing nodes as subnodes. To create an
element, a reference variable document with type
IF_IXML_DOCUMENT (pointing to an XML document) can be used to
call the following method:
element = document- create_element_ns( name = ... ).
The static type of the reference variable element is then
IF_IXML_ELEMENT and it points to an
element called name that is not yet part of the tree structure.
The following call can be used to insert the element in the tree
structure:
parent- append_child( element ).
Here, parent is a reference variable that points to an existing
node object of the XML document. A reference variable,
document , can be specified for parent for the document itself
as an access point to an empty document.
The elements created using CREATE_ELEMENT_NS are empty. The
following method can be used to create content:
DATA(text) = document- create_text( ... ) .
The static type of the reference variable text is then
IF_IXML_TEXT and it points to
literal content that is not yet part of the tree structure. This can be
inserted in an element using the method APPEND_CHILD .
Adding Elements
The steps above used to add content to an element
create element
add element
create content
add content
can also be performed using a single method call as follows:
element = document->create_simple_element_ns(
name = ...
value = ...
parent = ... ).
This creates the element, with the content passed to value , and
appends it to the node passed to parent as a subnode. For this
reason, the individual steps described above are generally only used for
more specific tasks.
Adding Attributes
The following method can be used to add an attribute to an element of an
XML pointed to by a reference variable, element :
element- set_attribute_ns( name = ... value = ... ).
This creates an attribute called name with the value passed to
value .
Examples
See:
Creating Nodes
Creating Elements
Documentation extract taken from SAP system, � Copyright SAP AG. All rights reserved