public string ToString(string format, IFormatProvider formatProvider)
{
if (formatProvider == null)
{
formatProvider = new DOTFormatProvider();
}
var formatter = (ICustomFormatter)formatProvider.GetFormat(typeof(ICustomFormatter));
return(formatter.Format(format, this, formatProvider));
}
public string Format(string format, object arg, IFormatProvider formatProvider)
{
if (formatProvider == null)
{
formatProvider = new DOTFormatProvider();
}
if (arg is Vertex v)
{
switch (format.Replace("X", "").Replace("L", "").Replace("W", ""))
{
case "GV":
return("\"" + v.ID.ToString() + "\\n(" + v.Value.ToString() + ")\"");
case "VG":
return("\"" + v.Value.ToString() + "\\n(" + v.ID.ToString() + ")\"");
case "V":
return("\"" + v.Value.ToString() + "\"");
case "G":
default:
return(v.ID.ToString());
}
}
else if (arg is Edge e)
{
string attr = "";
switch (format.Replace("X", "").Replace("G", "").Replace("V", ""))
{
case "LW":
attr = " [label=\"" + e.Label + "\\n(" + e.Weight.ToString() + ")\"]";
break;
case "WL":
attr = " [label=\"" + e.Weight.ToString() + "\\n(" + e.Label + ")\"]";
break;
case "W":
attr = " [label=\"" + e.Weight.ToString() + "\"]";
break;
case "L":
attr = " [label=\"" + e.Label + "\"]";
break;
default:
attr = "";
break;
}
return(e.Tail.ToString(format, formatProvider) + Edge.ToDirectedDOTNotation(e.Directed) + e.Head.ToString(format, formatProvider) + attr);
}
else if (arg is Graph g)
{
StringBuilder sb = new StringBuilder();
HashSet <int> labeledVertices = new HashSet <int>();
sb.AppendLine((g.DirectedEdgeCount > 0 ? "di" : "") + "graph " + g.Name + " {");
sb.AppendLine(" node [fontsize = \"12\"];");
sb.AppendLine(" edge [fontsize = \"8\"];");
foreach (var edge in g.Edges.Values)
{
if (format.Contains("X"))
{
labeledVertices.Add(edge.Tail.ID);
labeledVertices.Add(edge.Head.ID);
}
sb.AppendLine(" " + edge.ToString(format, formatProvider) + ";");
}
foreach (var id in labeledVertices)
{
sb.AppendLine(" " + id.ToString() + " [label=\"" + g.Vertices[id].Value.ToString() + "\"];");
}
sb.AppendLine("}");
return(sb.ToString());
}
else
{
throw new ArgumentException("Unsupported argument type.", "arg");
}
}
