[cokacola]

Note: This tutorial assumes you have basic knowledge of C#, such as variables, referencing and methods!
Download LuaInterface
Hello, today I will be posting this tutorial on integrating Lua with C# using the LuaInterface library(including adding custom Lua functions).
So, to get this library, first visit this page: http://luaforge.net/...s/luainterface/.
Now, on this page, scroll down a little and you should see "Latest File Releases".
Under this will be a download link for LuaInterface, click the link and you will be redirected to a page where the item you chose to download is highlighted.
Click the filename for it and the file will download.

(In the image above, you can see I drew a box around the filename).
Once the file has finished, extract the 2 DLL files inside(one of them will be LuaInterface.dll and the other will be something like Lua51.dll) to a folder on your hard-drive(they must be in the same folder, as referencing LuaInterface also copies the other DLL to your output directory).
Create a new project and Reference LuaInterface
Okay, so now that we've downloaded LuaInterface, its time to do something with it.
First off, create a new C# Console program and name it what ever you want.
Now, for this tutorial, I will assume you know how to reference libraries in C#, so go ahead and reference LuaInterface.dll, the other DLL should be copied to your output folder with it.
Okay, now at the top of your document, copy these using statements:

using System;
using LuaInterface;
using System.IO;
using System.Timers;

As you can see, I added LuaInterface in there, but I also added System.IO and System.Timers.
I included System.IO because we will be going over loading .lua script files.
I included System.Timers because I will be showing you a basic Lua timer function.
Running basic strings
Okay, now that we have it referenced, add this above your Main method:

private static Lua lua = new Lua();

The reason we put this outside the Main method is that we will be using it outside the Main method.
Now, we could set a basic Lua variable like this(this can go inside the Main method)

lua.DoString("myvar = 25")

This will set a myvar variable for this session to 25.
To access this variable, you can do this:

double myvar = (double)lua["myvar"];

(note: this has to be a double, an int throws an exception)
See, its not too hard.
Running files
Okay, now that I've showed you how to execute a Lua string, I will show you how to do the same thing, but with loading a file instead.
In your programs output folder(either Debug or Release, if its a new project than it will probably be Debug), create a new file called "script.lua", and put this inside it:

myvar = 25

Now, back to C#: Inside the Main method, put this:

lua.DoFile("script.lua");

This will load the file, and for the session, set MyVar to 25.
Now, we can use the variable like this:

double something = (double)lua["myvar"];

(Note: this has to be a double, an int throws an exception)
Just put that under the Lua.DoFile inside your main method, and it should work.
Now, under that code, we could put this:

Console.WriteLine(something);
Console.ReadKey(); //wait for key input to exit the program, so it doesn't quit before you can read the value

Load all Lua files from a script folder
Okay, now, I will be showing you a quick snippet to load all files ending with ".lua" in a script folder.
In your output directory, make a new folder called "scripts".
Now, you can put this code in your Main method to load and run all .lua files from the scripts folder:

foreach(string st in Directory.GetFiles("scripts\\","*.lua",SearchOption.AllDirectories)) {
	try {
		lua.DoFile(st);
	} catch(Exception err) {
		//This occures if there the file could not be loaded.
		//This happens mostly if there is an error in the lua script, so you might want to output it or something.
	}
}

Note: when including lua files from other lua files, you can't just use "script.lua" it must be "scripts/script.lua".
Adding custom Lua functions
Yes, here it is, the part you've all been waiting for( ), adding new Lua functions!
Okay, now at the top of your Main method, add this line:

Program program = new Program();

This is required for when you register a Lua function.
Now, lets create a new method under Main called "outString":

public static void outString(string line) {
	Console.ForegroundColor = ConsoleColor.Yellow;
	Console.WriteLine(line);
	Console.ResetColor();
}

This will soon become a Lua function, and as you can see, it will output a line of text(in yellow), to the Console window of your program.
Now that we have that, lets get back to the Main method.
To register our method as a Lua function, we use this line:

lul.RegisterFunction("outString",program,program.GetType().GetMethod("outString"));

Now, in your Lua script, you can do this:

outString("I am in the console now!")

How cool is that?!
A timer function for you
I made a timer function, its simple, and doesn't work with arguments, but its cool anyway.
Here is the method:

public static void setTimer(string func,double ms) {
	System.Timers.Timer sttime = new System.Timers.Timer(ms);
	sttime.Start();
	sttime.Elapsed += delegate(object sender, ElapsedEventArgs e) {
		LuaFunction fnc = lul.GetFunction(func);
		fnc.Call();
		sttime.Stop();
	};
}

And here is the register line(for the main method)

lul.RegisterFunction("setTimer",program,program.GetType().GetMethod("setTimer"));

That concludes this tutorial, I hope this helps you guys out

[petastream]

Very cool, I've had this as a back burner thought for the project that I am currently working on at my work. Thank you for the intro howto.