Using XML Parameter Values
The HTMLQuestion,ExternalQuestion, QuestionForm, QuestionFormAnswers, and AnswerKey data structures are used as parameter values in service requests, and as return values in service responses. Unlike other data structures described in this API reference, these XML structures are not part of the service API directly, but rather are used as string values going in and out of the service. This article describes the encoding methods needed to use XML data as parameter and return values.
XML Data as a Parameter
Data must be URL encoded to appear as a single
parameter value in the request. Characters that are
part of URL syntax, such as question marks (?
) and ampersands
(&
), must be replaced with the corresponding URL character
codes.
Note
XML data should only be URL encoded, not XML escaped.
In service responses, this data will be XML escaped.
Namespaces for XML Parameter Values
XML data in parameter values must have a namespace specified for all elements. The easiest way
to do this is to include an xmlns
attribute in the root element equal to the
appropriate namespace.
The namespace for a HTMLQuestion
,ExternalQuestion
, QuestionForm
,
QuestionFormAnswers
, or AnswerKey
element is
identical to the URL of the corresponding schema document, including the version date. While XML
namespaces need not be URLs according to the XML specification, this convention ensures that the
consumer of the value knows which version of the schema is being used for the data.
For the locations of the schema documents, as well as instructions on how to include the version date in the URL, see Schema Locations.