Delphi XML binding wizard and optional elements

3
votes

In my XSD I have:

  <xs:complexType name="scheduleLocation">
    <xs:sequence>
      <xs:element name="arrivalTime" type="hhmmss" default="00:00:00" minOccurs="0"/>
      <xs:element name="departureTime" type="hhmmss" default="00:00:00" minOccurs="0"/>
      <xs:element name="passingTime" type="xs:boolean" default="false" minOccurs="0"/>
    </xs:sequence>
  </xs:complexType>

Meaning that the following XML extract is valid:

<scheduleLocation>
  <arrivalTime>07:33:00</arrivalTime>
  <departureTime>07:34:00</departureTime>
</scheduleLocation>

(ie no passing time node)

Using the D6 XML Data Binding Wizard I get:

function TXMLScheduleLocation.Get_PassingTime: Boolean;
begin
  Result := ChildNodes['passingTime'].NodeValue;
end;

Of course, if I try to get the passing time value then it crashes where passingTime is not specified in the XML. Is there any way around this - some trick with the wizard? Also, I think the default value is ignored. Am I going to have to hand edit the results?

Incidentally xsd.exe generates xxxSpecified fields which would have helped here.

1
xmldelphidata-binding

1 Answers

2
votes

AFAIK, the XML Databinding wizard does not take into account default values, you have to code them by hand:

function TXMLScheduleLocation.Get_PassingTime: Boolean;
begin
 if ChildNodes['passingTime'].NodeValue = null then
  Result := false
 else
  Result := ChildNodes['passingTime'].NodeValue;
end;