xmlXPath
Make a XPath query on a XML document
Syntax
result = xmlXPath(xmlObj, queryStr) result = xmlXPath(xmlObj, queryStr, namespaces)
Arguments
- xmlObj
a XML mlist typed XMLDoc or XMLElem
- queryStr
a Xpath query
- namespaces
An optional matrix nx2 of strings
- result
result can be a set of XMLElements or a number or a string or a boolean
Description
Make a XPath query on a document or in starting on an element. If you need to use namespaces, then you must define them in using the optional argument. XML namespaces are defined in the first tag with the keyword "xmlns".
For more information about XPath, you can read the W3C recommendation.
Examples
doc = xmlRead("http://www.w3.org/TR/2009/REC-xml-names-20091208/xml-names-10-3e.xml"); // Retrieve the nodes with name equal to "note" xp = xmlXPath(doc, "//note"); s = size(xp); for i=1:s(2) xmlDump(xp(i)) end // Count the nodes with name equal to "note" xp = xmlXPath(doc, "count(//note)") // Retrieve the node with id="Philosophy" xp = xmlXPath(doc, "//*[@id=""Philosophy""]"); s = size(xp); if (s(2) <> 0) then xmlDump(xp(1)) end // Retrieve the nodes with an attribute num equal to the number 5 xp = xmlXPath(doc, "//*[number(@num)=5]"); s = size(xp); if (s(2) <> 0) then xmlDump(xp(1)) end // Get the name and the content of all the attributes of nodes named 'emph' xp = xmlXPath(doc, "//emph/@*"); xp.name xp.content xmlDelete(doc); // Query using namespaces t = "<root xmlns:scilab=""http://www.scilab.org"">"+.. "<scilab:a att=""foo"" rib=""bar"">"+.. "<b>Hello</b></scilab:a></root>" doc = xmlReadStr(t); // We search for element named a xmlXPath(doc, "//a") // => nothing xmlXPath(doc, "//scilab:a", ["scilab" "https://www.scilab.org"]) // => OK // This code will fail: // xmlXPath(doc, "//scilab:a") // => error xmlDelete(doc); // Query starting on an element t = "<root att=""attribute""><a a1=""A1"" a2=""A2"" a3=""A3"">"+.. "<b>Hello</b><c>Scilab</c><b>World</b></a><b>Nothing</b></root>" doc = xmlReadStr(t); e = doc.root.children(1); // Get the attributes of e xp = xmlXPath(e, "@*"); xmlAsText(xp) // Get the 'b' from e xp = xmlXPath(e, "b"); xmlAsText(xp) xmlDelete(doc);
Getting the XML comments:
doc = xmlRead(SCI+"/modules/ui_data/etc/newsfeed.xml"); c = xmlXPath(doc, "//comment()"); // do not forget the trailing () c.content' xmlDelete(doc);
--> c.content' ans = ! RSS Feed URL ! ! automatic news change interval time (in ms), set to -1 to disable ! ! periodic feed update interval time (in ms), set to -1 to disable !
See also
History
Версия | Описание |
5.4.0 | XML module introduced. |
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