LUA:Money System Part 1

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Lua: Money System

Description:	A simple tutorial on how to create a basic money system.
Original Author:	KillerLUA
Created:	March 12, 2010

Contents 1 Introduction 2 Requirements 3 Setting up the files 4 Meta Usage

Introduction

In this tutorial, I'm going to tell you how to create a basic money system in your garrys mod gamemodes. In a later tutorial, I will show you how to get a basic money hud working. For now, Let's get started on our money system!

Requirements

Knowledge Prior to Using the Tutorial:

- A pre-coded gamemode

- Some Lua experience

- A brain

What you're going to learn:

- How to use meta tables

- Adding new functions to meta tables

- How to store and get networked integers (whole numbers)

- A simple way of saving variables

Setting up the files

First, we are going to create a new file in our gamemode called 'sh_player.lua'

Next, we want the file included by the client and the server.

Add the following lines of code to init.lua (Serverside code of your gamemode):

 
include( 'sh_player.lua' )
AddCSLuaFile( "sh_player.lua" )
 

include( 'sh_player.lua' ) - Includes the file, including all it's functions. The code is also run on the server start AddCSLuaFile( "sh_player.lua" ) - Makes the player download the clientside file

Then, add these lines to cl_init.lua (Clientside code of your gamemode):

 
include( 'sh_player.lua' )
 

Used the same way as above.

Meta Usage

Now, go to your sh_player.lua file, add the following code. Then, I'll explain it's usage.

 
local meta = FindMetaTable("Player") --Get the meta table of player
 

Basicly, we define meta with all the functions that can be called via ply:SomeFunction()

To add functions, we use simple code like this:

 
local meta = FindMetaTable("Player") --Get the meta table of player
 
function meta:WowFunction(command)
     self:ConCommand(command)
     self:ChatPrint("Wow function ran the console command: " .. tostring(command))
end
 

Now, we can call it like any ordinary player function!

 
ply = LocalPlayer()
ply:WowFunction()
 

This is how are cash function is going to work, first we are going to draw up a list of functions:

player.SetMoney( amount )

player.GetMoney()

player.AddMoney( amount )

player.TakeMoney( amount )

player.SaveMoney()

player.SaveMoneyTXT()

Let's begin by coding all these functions,

First, the set money function,

 
function meta:SetMoney(amount)
	self:SetNetworkedInt( "Money", amount )
	self:SaveMoney()
end
 

Now, we will add the get money function

 
function meta:SetMoney(amount)
	self:SetNetworkedInt( "Money", amount )
	self:SaveMoney()
end
 
function meta:GetMoney()
	return self:GetNetworkedInt( "Money" )
end
 

Now, for the add money function. Which basicly calls the set money function.

 
function meta:SetMoney(amount)
	self:SetNetworkedInt( "Money", amount )
	self:SaveMoney()
end
 
function meta:GetMoney()
	return self:GetNetworkedInt( "Money" )
end
 
function meta:AddMoney(amount)
	local current_cash = self:GetMoney()
	self:SetMoney( current_cash + amount )
end
 

To finalize everything on meta usage, here is the full code:

 
local meta = FindMetaTable("Player") --Get the meta table of player
 
function meta:AddMoney(amount)
	local current_cash = self:GetMoney()
	self:SetMoney( current_cash + amount )
end
 
function meta:SetMoney(amount)
	self:SetNetworkedInt( "Money", amount )
	self:SaveMoney()
end
 
function meta:SaveMoney()
	local cash = self:GetMoney()
	self:SetPData("money", cash)
end
 
function meta:SaveMoneyTXT()
	file.Write(gmod.GetGamemode().Name .."/Money/".. string.gsub(self:SteamID(), ":", "_") ..".txt", self:GetMoneyString())
end
 
function meta:TakeMoney(amount)
   --Add money function here
   self:AddMoney(-amount)
end
 
function meta:GetMoney()
	return self:GetNetworkedInt( "Money" )
end
 

Now continue to part two on how to finish it off. I will also give an example of how it can be used.

Back to KillerLUA Tutorials

Part 2