c# language issue: when you need to serialize/deserialize a user defined Func/Action

BillWoodruff

okay, we know that's not possible via the usual save/restore techniques for damn good reasons: 1) Func and Action (delegates) can have references to external objects/states the compiler can't resolve. 2) if that could be done, it would be an ideal way to insert/execute malicious code. as i see it, now, that leaves two alternatives: 1) have some kind of plug-in architecture that exposes pre-defined delegates. but, that could also be vulnerable to security threats. more critical would be the delegates defined in the plug-in need for access/reference to the definitions/references of internal objects in the app it would manipulate. 2) a DSL/script-language that could be saved/restored as text, and then compiled via Roslyn reflection/emit, etc. a concrete example of the type of Func i'd iike to save:

private static readonly Random rand = new Random();

private double IntensityFunc(Edge edge)
{
var hour = DateTime.Now.Hour;

if (hour > 3 && hour < 12) return edge.IntensityMin;

if (hour > 22) return edge.IntensityMax;

return rand.NextDouble() \* (edge.IntensityMax - edge.IntensityMin) + edge.IntensityMin;

}

mini-example showing Node and Edge definitions, and Func usage:

// node or vertex
public class Node: INode // interface not shown
{
public Node(string name, int id)
{
Name = name;
Id = id;
}

public string Name { set; get; }

public string Id { set; get; }

}

// an edge describes a connection between two nodes
public class Edge: IEdge // interface not shown
{
public Edge(Node node1, Node node2, double intensity, double intensityMin = 0.0, double intensityMax = 0.0,
Func intensityFunc = null)
{
Node1 = node1;
Node2 = node2;
Intensity = intensity;
IntensityMin = intensityMin;
IntensityMax = intensityMax;
IntensityFunc = intensityFunc;
}

public Node Node1 { set; get; }

public Node Node2 { set; get; }

public double Intensity { set; get; }

public double IntensityMin { set; get; }

public double IntensityMax { set; get; }

public Func IntensityFunc { set; get; }

public double GetIntensity()
{
    return IntensityFunc?.Invoke(this) ?? Intensity;
}

}

// usage example
private void Form1_Load(object sender, EventArgs e)
{
var Jack = new Node("Jack", 1);

var Jill = new Node("Jill", 2);

var JackToJill = new Edge(Jac