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Working with XML
Reading XML Documents with the Simple API for XML (SAX) : Understanding ABL SAX : SAX-attributes object : Creating a SAX-attributes object
 
Creating a SAX-attributes object
Use the CREATE SAX-ATTRIBUTES statement to create an instance of a SAX-attributes object and assign its handle to the handle variable specified.

Syntax

CREATE SAX-ATTRIBUTES handle[ IN WIDGET-POOL pool-name][ NO-ERROR ]
handle
Variable of type HANDLE which stores the handle of the new SAX-attributes object.
IN WIDGET-POOL pool-name
Specifies the widget pool where the AVM creates the new object. If you do not specify a widget pool, the AVM creates the object in the current default widget pool.
NO-ERROR
Specifies that the AVM should suppress errors occurring during the creation of the SAX-attributes handle. After the CREATE SAX-ATTRIBUTES statement completes, you can check the ERROR-STATUS system handle for information about errors that might have occurred.
In ABL, a SAX-attributes object can be automatically created and managed by the SAX parser, or programatically created and managed by you. Automatic SAX-attributes objects are created, populated, and destroyed during the scope of the StartElement callback procedure. The StartElement callback is called by the SAX-reader object each time the SAX parser encounters a new XML element during a read operation. The SAX parser populates the SAX-attributes object, but you may interact with the object during the scope of the StartElement callback procedure. For example, you may add elements, update elements, and remove elements from the SAX-attributes object.
At the conclusion of the callback, the SAX-attributes object is deleted and your access to the element list is lost. To save the XML attributes list, you would need to create another SAX-attributes object that is not tied to the scope of the StartElement callback procedure. Then, from within the StartElement callback, you would use the COPY-SAX-ATTRIBUTES( ) method on the new object and provide the handle to the automatically created SAX-attributes object, which is the attributes input parameter of the StartElement callback. Finally, you would likely pass the XML element and its attributes to another procedure outside of the callback's scope for further processing.
The SAX-writer also supports use of the SAX-attributes object. Here, you could pass it a copy of an attribute list from an XML element, or you might define a SAX-attributes object that contains a standard set of attribute values to apply to particular XML elements output by the SAX-writer object.
For an example of using a user-created SAX-attributes object, see Writing XML Documents with the Simple API for XML (SAX).