HasXPath Method
Checks whether a certain XPath exists inside the aggregate.
Syntax
ofxaggregate.hasXPath(XPath, [callback])
Callback
The 'callback' parameter specifies a function which will be called when the operation completes (or an error is encountered). If the 'callback' parameter is not specified, then the method will block and will not return until the operation completes (or an error is encountered).
The callback for this method is defined as:
function(err, data){ }
'err' is the error that occurred. If there was no error, then 'err' is 'null'.
'data' is the value returned by the method.
'err' has 2 properties which hold detailed information:
err.code err.message
Remarks
Used when there is no assurance that a certain XPath exists inside an aggregate.