XPathError class

An XPathError exception can be thrown by various methods in the XmlDoc API. It indicates an error either in the syntax of an XPath argument to the method, or in the results returned by that XPath expression. The various read-only properties of an XPathError object (which can be set by the Catch statement) provide information about the failed operation.

An example of using the XPathError exception is:

%err Object XPathError Try %d:Print('a b c') Catch XPathError To %err PrintText {~} = {%err:Reason} PrintText {~} = {%err:Description} PrintText {~} = {%err:CharacterPosition} End Try

Since the expression in the above invocation of the Print method (a b c) is not a valid XPath expression, the above fragment will result in the following:

%err:Reason = SyntaxError %err:Description = Expect "/" for new step or "[" for predicate %err:CharacterPosition = 3

This class is new in version 7.8 of the Sirius Mods.

The XPathError methods

The following are the available XPathError class methods.

Method	Description
CharacterPosition	Position of character at of before which the error occurred
Description	Brief description of the exception
New	Create a new XPathError object
Reason	Enumerated cause of the exception

The methods in the class are described in the subsections that follow. In addition:

• "Notation conventions for methods" has information about the conventions followed.
• "XPathError methods syntax" is a single page that contains the syntax diagrams of all the methods in the class.