Xml Serialization

Xml Serialization

QuikGraph supports loading and saving graphs to and from Xml. The implementation builds on top of XmlReader and XmlWriter and is located in the SerializationExtensions class from the QuickGraph.Serialization module.

Serializing graphs

To serialize a graph, call the SerializeToXml extension methods with an XmlWriter instance and delegates that can map vertices and edges to an identifier string. The serialization method also supports custom delegate to write additional information per vertex, edge.

class MyVertex
{
    public int ID { get; set; }
}

class MyEdge : IEdge<MyVertex>
{
    string Name { get; set; }
    string Tag { get; set; }
}

var graph = new AdjacencyGraph<MyVertex, MyEdge>();
...
using (var writer = XmlWriter.Create(...))
{
    graph.SerializeToXml(
        writer,
        v => v.ID, // Let's use ID as the vertex ID
        AlgorithmExtensions.GetEdgeIdentity(graph), // Let QuikGraph give an id to edges
        "graph", "myvertex", "myedge", "" // names of the graph, vertex, edge, node xml tags and the namespace uri
    );
}

Deserializing graphs

To deserialize a graph, call the DeserializeFromXml extension methods with an XmlReader or an IXPathNavigable instance. The result of the method will be the deserialized graph instance.

using (var reader = XmlReader.Create(...))
{
    AdjacencyGraph<string, Edge<string>> graph = reader.DeserializeFromXml(
        "graph", "myvertex", "myedge", "", // names of the graph, vertex, edge, node xml tags and the namespace uri
        _ => new AdjacencyGraph<string, Edge<string>>(),
        r => r.GetAttribute("id"),
        r => new Edge<string>(
            r.GetAttribute("source") ?? throw new ArgumentException("Must have source attribute"),
            r.GetAttribute("target") ?? throw new ArgumentException("Must have target attribute")));

    ...
}

Serializing Custom Fields

The serializer supports the delegates to write additional information of the vertex, edge and graph types.