Formatting API

The Formatting API is an collection of APIs found in the VDS.RDF.Writing.Formatting namespace, it is concerned with turning objects like nodes, triples and SPARQL results into strings for display. The formatting API underpins the writers already seen in the basic tutorial on the Writing RDF page.

The API consists of a number of interfaces:

Interface	Formatting Capabilities
ICharFormatter	Formats individual characters
IUriFormatter	Formats URIs
IBaseUriFormatter	Formats Base URI declarations
INamespaceFormatter	Formats namespace declarations
INodeFormatter	Formats INode instances
ITripleFormatter	Formats Triple instances
IResultFormatter	Formats SparqlResult instances

Basic Usage

Generally you will only want to use one of the higher level interfaces such as INodeFormatter or ITripleFormatter. Both these interfaces define Format(…) methods which take either a Triple or an INode and return a string representation of them. You can also call ToString(…) overloads on Triple and INode which take in a formatter and return the String representation as formatted by that formatter.

In general any formatter usually provides one or more Format() or FormatX() methods which are used to format specific things. These methods take the thing to be formatted and return a string.

Example 1

For example we can format specific nodes:

//Assumes that we already have a Graph in the variable g
NTriplesFormatter formatter = new NTriplesFormatter();

//Want to get only the triples defining types - assumes rdf: prefix is appropriately defined for this Graph
UriNode rdfType = g.CreateUriNode("rdf:type");

//This prints only the subjects of the Triples we find with
//the predicate rdf:type using NTriples formatting
foreach (Triple t in g.GetTriplesWithPredicate(rdfType))
{
	Console.WriteLine(t.Subject.ToString(formatter));
}

Standard Implementations

Currently the library has the following formatters available but you can easily define your own:

Formatter	Format Produced
CsvFormatter	CSV
Notation3Formatter	Notation 3
NQuadsFormatter	NQuads
NTriplesFormatter	NTriples
SparqlFormatter	SPARQL style, can also format queries
TsvFormatter	TSV
TurtleFormatter	Turtle
UncompressedNotation3Formatter	Uncompressed Notation 3
UncompressedTurtleFormatter	Uncompressed Turtle

Example 2

Here's another example of formatting Triples for display on the console:

using System;
using System.Collections.Generic;
using System.Linq;
using VDS.RDF;
using VDS.RDF.Writing.Formatting;

public class FormattingTriplesExample
{
  public static void Main(String[] args)
  {
    IGraph g = new Graph();

    //Assume we fill our graph with data from somewhere...

    //Create a formatter
    ITripleFormatter formatter = new TurtleFormatter(g);

    //Print triples with this formatter
    foreach (Triple t in g.Triples)
    {
      Console.WriteLine(t.ToString(formatter));
    }
  }
}