Nexbox

A Simple C# Sandboxing Library Supporting Multiple Languages

How to use

1. Select your target framework

   • net48/Nexbox.dll for net48
   • net6.0/Nexbox.dll for net6.0

2. Import the reference

3. Create a new IInterpreter

   • NOTE: You MUST know what language the code is in!

// Our code to execute (this does not have to be a constant)
const string CODE = "local sum = 10 + 20 \r\n" +
                    "print(sum)";

// This code is in lua because of the local declaration
IInterpreter interpreter = new LuaInterpreter();
/*
 * Essentially what initializes the Sandboxing environment
 * The first and only parameter is where to direct print functions
*/
interpreter.StartSandbox(Console.WriteLine);
// Execute the code. This can be ran multiple times.
interpreter.RunScript(CODE);
// Call Stop when you're done with the interpreter
interpreter.Stop();

Creating Global Values

You can create global values by using the IInterpreter.CreateGlobal(string name, object global) method

// Typically, you would use JavaScript's Math.PI; however, for the example, we will make our own
const string CODE = "let sum = pi + 20 \r\n" +
                    "print(sum)";

// This code is in JavaScript because of the let declaration
IInterpreter interpreter = new JavaScriptInterpreter();
interpreter.StartSandbox(Console.WriteLine);
// Create our pi global
interpreter.CreateGlobal("pi", Math.PI);
interpreter.RunScript(CODE);
interpreter.Stop();

Creating Reference Types

In some scenarios, you may want to share classes with the interpreter. PLEASE MAKE SURE THESE CLASSES ARE SAFE TO SHARE!

In this example, we create our own data object, then pass it to the interpreter to use.

const string LUA_CODE = "local person = PersonData() \r\n" +
                        "person.Name = \"Joe\" \r\n" +
                        "person.Age = 42 \r\n" +
                        "print(person.Name..\" is \"..tostring(person.Age)..\" years old!\")";
const string JS_CODE = "let person = new PersonData() \r\n" +
                       "person.Name = \"Amy\" \r\n" +
                       "person.Age = 25 \r\n" +
                       "print(person.Name + \" is \" + person.Age + \" years old!\")";
// Parameter Constructors can be utilized in JavaScript
// When running a Script under the same interpreter, be sure to change variable names!
const string JS_CODE2 = "let person2 = new PersonData(\"Michael\", 17) \r\n" +
                        "print(person2.Name + \" is \" + person2.Age + \" years old!\")";

IInterpreter lua = new LuaInterpreter();
IInterpreter js = new JavaScriptInterpreter();
lua.StartSandbox(Console.WriteLine);
js.StartSandbox(Console.WriteLine);
lua.ForwardType("PersonData", typeof(PersonData));
js.ForwardType("PersonData", typeof(PersonData));
lua.RunScript(LUA_CODE);
js.RunScript(JS_CODE);
js.RunScript(JS_CODE2);
lua.Stop();
js.Stop();

public class PersonData
{
    public string Name;
    public int Age;

    public PersonData(){}
    public PersonData(string Name, int Age)
    {
        this.Name = Name;
        this.Age = Age;
    }
}

NOTE: All types passed into IInterpreter.ForwardType(string, Type) will make the type need to be created.

For JavaScript, do

let obj = new Type()

and for Lua, do

local obj = Type()