The SelectNode function compiles the XPath expression and then executes it with the node as a context node, and returns the result as a single XPathNode, the node that makes the first hit. The function can optionally take in XPath variables.
SelectNode(Parameters
- query
- The expression query.
- variables
- This is optional parameter with default value nil.
This parameter takes in XPathVariableSet to use in the query.
Returns
- EinhugurXml.XPathNode
- XPathNode which can carry either Node or Attribute depending on the Query.
Remarks
Note that XPathNode can carry either Node or Attribute.
This function can throw EinhugurXPathException.
Example:
var xnode as EinhugurXml.XPathNode = doc.SelectNode("//Tool[contains(Description, 'build system')]")
if xnode <> nil then
MessageBox xnode.Node.ToString()
end if
While compiling expressions is fast, the compilation time can introduce a significant overhead if the same expression is used many times on small subtrees. If you’re doing many similar queries, consider compiling them into query objects. Once you get a compiled query object, you can pass it to select functions instead of an expression string.