C# directed graph generating library

Question

I noticed that Visual Studio can generate graphs using something called DGML.

I would like to generate a graph like the following one in my C# application.

It does not have to be interactive like the VS. I just want to generate a static such image and save it as a general graphics file, such as PNG.

Is there any free .NET library for this?

Answer 1

A little late, but it's actually relatively easy to implement yourself:

public class DGMLWriter
{
    public struct Graph
    {
        public Node[] Nodes;
        public Link[] Links;
    }

    public struct Node
    {
        [XmlAttribute]
        public string Id;
        [XmlAttribute]
        public string Label;

        public Node(string id, string label)
        {
            this.Id = id;
            this.Label = label;
        }
    }

    public struct Link
    {
        [XmlAttribute]
        public string Source;
        [XmlAttribute]
        public string Target;
        [XmlAttribute]
        public string Label;

        public Link(string source, string target, string label)
        {
            this.Source = source;
            this.Target = target;
            this.Label = label;
        }
    }

    public List<Node> Nodes { get; protected set; }
    public List<Link> Links { get; protected set; }

    public DGMLWriter()
    {
        Nodes = new List<Node>();
        Links = new List<Link>();
    }

    public void AddNode(Node n)
    {
        this.Nodes.Add(n);
    }

    public void AddLink(Link l)
    {
        this.Links.Add(l);
    }

    public void Serialize(string xmlpath)
    {
        Graph g = new Graph();
        g.Nodes = this.Nodes.ToArray();
        g.Links = this.Links.ToArray();

        XmlRootAttribute root = new XmlRootAttribute("DirectedGraph");
        root.Namespace = "http://schemas.microsoft.com/vs/2009/dgml";
        XmlSerializer serializer = new XmlSerializer(typeof(Graph), root);
        XmlWriterSettings settings = new XmlWriterSettings();
        settings.Indent = true;
        using (XmlWriter xmlWriter = XmlWriter.Create(xmlpath, settings))
        {
            serializer.Serialize(xmlWriter, g);
        }
    }
}