Class SparqlExpressionFactory

Factory Class for generating Expressions for Sparql Extension Functions.

Inheritance

object

SparqlExpressionFactory

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: VDS.RDF.Query.Expressions

Assembly: dotNetRdf.dll

Syntax

public static class SparqlExpressionFactory

Remarks

Allows for users of the Library to implement and register Custom Expression Factories which can generate Expressions for their own Extension functions which they wish to use in their SPARQL queries. Custom factories may be globally scoped by registering them with the AddCustomFactory() method or locally by passing them to the four argument constructor of the CreateExpression() method.

Properties

Factories

Gets the Global Custom Expression Factories that are in use.

Declaration

public static IEnumerable<ISparqlCustomExpressionFactory> Factories { get; }

Property Value

Type	Description
IEnumerable<ISparqlCustomExpressionFactory>

Methods

AddCustomFactory(ISparqlCustomExpressionFactory)

Registers a Custom Expression Factory.

Declaration

public static void AddCustomFactory(ISparqlCustomExpressionFactory factory)

Parameters

Type	Name	Description
ISparqlCustomExpressionFactory	factory	A Custom Expression Factory.

CreateExpression(Uri, List<ISparqlExpression>, bool)

Tries to create an Expression from the given function Uri and list of argument expressions.

Declaration

public static ISparqlExpression CreateExpression(Uri u, List<ISparqlExpression> args, bool allowUnknownFunctions)

Parameters

Type	Name	Description
Uri	u	Function Uri.
List<ISparqlExpression>	args	List of Argument Expressions.
bool	allowUnknownFunctions	Specifies whether functions that cannot be parsed into expressions should be represented by the UnknownFunction.

Returns

Type	Description
ISparqlExpression

Remarks

Uses only the globally scoped custom expression factories.

CreateExpression(Uri, List<ISparqlExpression>, Dictionary<string, ISparqlExpression>, IEnumerable<ISparqlCustomExpressionFactory>, bool)

Tries to create an Expression from the given function Uri and list of argument expressions.

Declaration

public static ISparqlExpression CreateExpression(Uri u, List<ISparqlExpression> args, Dictionary<string, ISparqlExpression> scalarArgs, IEnumerable<ISparqlCustomExpressionFactory> factories, bool allowUnknownFunctions)

Parameters

Type	Name	Description
Uri	u	Function Uri.
List<ISparqlExpression>	args	List of Argument Expressions.
Dictionary<string, ISparqlExpression>	scalarArgs	Scalar Arguments.
IEnumerable<ISparqlCustomExpressionFactory>	factories	Enumeration of locally scoped expression factories to use.
bool	allowUnknownFunctions	Specifies whether functions that cannot be parsed into expressions should be represented by the UnknownFunction.

Returns

Type	Description
ISparqlExpression

Remarks

Globally scoped custom expression factories are tried first and then any locally scoped expression factories are used.

CreateExpression(Uri, List<ISparqlExpression>, IEnumerable<ISparqlCustomExpressionFactory>, bool)

Tries to create an Expression from the given function Uri and list of argument expressions.

Declaration

public static ISparqlExpression CreateExpression(Uri u, List<ISparqlExpression> args, IEnumerable<ISparqlCustomExpressionFactory> factories, bool allowUnknownFunctions)

Parameters

Type	Name	Description
Uri	u	Function Uri.
List<ISparqlExpression>	args	List of Argument Expressions.
IEnumerable<ISparqlCustomExpressionFactory>	factories	Enumeration of locally scoped expression factories to use.
bool	allowUnknownFunctions	Specifies whether functions that cannot be parsed into expressions should be represented by the UnknownFunction.

Returns

Type	Description
ISparqlExpression

Remarks

Globally scoped custom expression factories are tried first and then any locally scoped expression factories are used.