This function parses an XML file into 2 parallel array
structures, one (index)
containing pointers to the location of the appropriate values
in the values array. These
last two parameters must be passed by reference.
Below is an example that illustrates the internal
structure of the arrays being generated by the function. We
use a simple note tag embeded inside
a para tag, and then we parse this
an print out the structures generated:
$simple = " para note simple note /note /para "; $p = xml_parser_create(); xml_parse_into_struct($p,$simple,$vals,$index); xml_parser_free($p); echo "Index array\n"; print_r($index); echo "\nVals array\n"; print_r($vals); |
Index array Array ( [PARA] = Array ( [0] = 0 [1] = 2 ) [NOTE] = Array ( [0] = 1 ) ) Vals array Array ( [0] = Array ( [tag] = PARA [type] = open [level] = 1 ) [1] = Array ( [tag] = NOTE [type] = complete [level] = 2 [value] = simple note ) [2] = Array ( [tag] = PARA [type] = close [level] = 1 ) ) |
Event-driven parsing (based on the expat library) can
get complicated when you have an XML document that is
complex. This function does not produce a DOM style object,
but it generates structures amenable of being transversed in
a tree fashion. Thus, we can create objects representing the
data in the XML file easily. Let's consider the following XML
file representing a small database of aminoacids
information:
** Database of AminoAcid objects: Array ( [0] = aminoacid Object ( [name] = Alanine [symbol] = ala [code] = A [type] = hydrophobic ) [1] = aminoacid Object ( [name] = Lysine [symbol] = lys [code] = K [type] = charged ) ) |