QualifiedType accessor to XML Schema type mapping

This previous post shows how WCF LOB Adapter SDK metadata object model can be used to define metadata for operations and/or types so that the WCF contract (WSDL) can be generated from it. The ResolveOperationMetadata() / ResolveTypeMetadata() methods in Microsoft.ServiceModel.Channels.Common.IMetdataResolverHandler implementation class are used to return the corresponding Microsoft.ServiceModel.Channels.Common.OperationMetadata / Microsoft.ServiceModel.Channels.Common.TypeMetadata, which in turn have knowledge generating equivalent XML Schema representation. This XML Schema is an integral part of the WSDL for defining the operation data structure.

The data types for an operation parameter, operation result and/or a complex object can be defined using the following two derived classes of the abstract class called Microsoft.ServiceModel.Channels.Common.QualifiedType.

- Microsoft.ServiceModel.Channels.Common.SimpleQualifiedType

- Microsoft.ServiceModel.Channels.Common.ComplexQualifiedType

The class QualifiedType defines static methods to get the instance for most commonly used types.

Let’s assume defining a simple operation named “Add” that takes in two parameters of type “double” and return a result of type “double”. The second double parameter has an extra restriction. The following code snippet shows using QualifiedType.DoubleType for parameter “n1” and result, but “n2” has an extra restriction to have a particular minimum length. The facets from System.Xml.Schema are used to define restrictions on various data types.

public class SampleAdapterMetadataResolverHandler : IMetadataResolverHandler

{

. . .

public OperationMetadata ResolveOperationMetadata(string operationId, TimeSpan timeout, out TypeMetadataCollection extraTypeMetadataResolved)

{

            extraTypeMetadataResolved = null;

            // for illustrative purposes show how to resolve one operation here

            ParameterizedOperationMetadata opMetadata = new ParameterizedOperationMetadata(operationId, operationId);

            opMetadata.OperationNamespace = SampleAdapter.SERVICENAMESPACE;

            opMetadata.OperationGroup = "SampleContract";

            // Syntax: double Add(double n1, double n2)

            opMetadata.DisplayName = "Add";

           // Create Parameters

           OperationParameter n1 = new OperationParameter("n1", OperationParameterDirection.In, QualifiedType.DoubleType, false);

          n1.Description = "First number to add.";

            // SimpleQualifiedType doubleSQT = new SimpleQualifiedType(System.Xml.Schema.XmlTypeCode.Double);

            SimpleQualifiedType doubleSQT = QualifiedType.DoubleType as SimpleQualifiedType;

            XmlSchemaMinLengthFacet minLengthFacet = new XmlSchemaMinLengthFacet();

            minLengthFacet.Value = "2";

            doubleSQT.XmlSchemaFacets.Add(minLengthFacet);

            OperationParameter n2 = new OperationParameter("n2", OperationParameterDirection.In, doubleSQT, false);

      n2.Description = "Second number to add.";

            opMetadata.Parameters.Add(n1);

            opMetadata.Parameters.Add(n2);

  // Create Result

  opMetadata.OperationResult = new OperationResult(QualifiedType.DoubleType, false);

           return opMetadata;

        }

    }

Use SimpleQualifiedType if you want to add additional restrictions on the type, as shown below, else just use the static member in QualifiedType to get the required type instance.

The following table shows the type mapping between the QualifiedType static type, XML Schema Type and generated Common Language Runtime (CLR) C# equivalent.

QualifiedType Member	XML Schema Type	C#	Target XML Schema Namespace
AnyType	xsd:anyType	Object	https://www.w3.org/2001/XMLSchema
Base64BinaryType	xsd: base64Binary	byte[]	https://www.w3.org/2001/XMLSchema
BooleanType	xsd: boolean	Bool	https://www.w3.org/2001/XMLSchema
ByteType	xsd:byte	Sbyte	https://www.w3.org/2001/XMLSchema
CharType	char	char	https://schemas.microsoft.com/2003/10/Serialization/
DateTimeType	xsd:dateTime	System.DateTime	https://www.w3.org/2001/XMLSchema
DecimalType	xsd:decimal	decimal	https://www.w3.org/2001/XMLSchema
DoubleType	xsd:double	double	https://www.w3.org/2001/XMLSchema
DurationType	duration	System.TimeSpan	https://schemas.microsoft.com/2003/10/Serialization/
FloatType	xsd:float	float	https://www.w3.org/2001/XMLSchema
GuidType	guid	System.Guid	https://schemas.microsoft.com/2003/10/Serialization/
IntType	xsd:int	int	https://www.w3.org/2001/XMLSchema
LongType	xsd:long	long	https://www.w3.org/2001/XMLSchema
QNameType	xsd:QName	System.Xml.XmlQualifiedName	https://www.w3.org/2001/XMLSchema
ShortType	xsd:short	short	https://www.w3.org/2001/XMLSchema
StreamType	StreamBody	System.IO.Stream (if used within OperationParameter and/or OperationResult) byte[] if used within TypeMember.	https://schemas.microsoft.com/Message
StringType	xsd:string	string	https://www.w3.org/2001/XMLSchema
UnsignedByteType	xsd:unsignedByte	byte	https://www.w3.org/2001/XMLSchema
UnsignedIntType	xsd:unsignedInt	uint	https://www.w3.org/2001/XMLSchema
UnsignedLongType	xsd:unsignedLong	ulong	https://www.w3.org/2001/XMLSchema
UnsignedShortType	xsd:unsignedShort	ushort	https://www.w3.org/2001/XMLSchema
UriType	xsd:anyUri	System.Uri	https://www.w3.org/2001/XMLSchema

Comments

• Anonymous
  May 14, 2009
  Thanks for the great posts Sonu. I have a quick question I am buiding a WCF for non WCF aware apps running on different technology. The operation contract accepts xml conforming to standard XML schema (like NIEM or HIPAA). Is LOB Adapter the best approach for this scenario. Also, is it possible for me to create a generic Adapter with generic Import and ExportXML methods for any schema. Thanks for your response

• Anonymous
  March 25, 2010
  plz clear me some more i mean how should i use this in wcf and java midlet

• Anonymous
  March 26, 2010
  @rakhi - What is your scenario? What are you trying to do? Are you creating a custom adapter?