Money System

[Hellray]

Alright, i've been trying to create a very small script to add a money system into sandbox
using networked integer's, everything is working fine except the add money on npc death thing. Here my code:

[LUA] function NPCkilled ( victim, killer, ply )
ply:GetNWInt( "money" )
if money == nil then
ply:SetNWInt( "money", 0 )
ply:SetNWInt( "money", "money" + 10 )
else
ply:SetNWInt( "money", "money" + 10 )
end
end

function Checkmoney( ply )
ply:GetNWInt( "money" )
if money == nil then
print( "You got no cash noob" )
else
print( money )
end
end

concommand.Add( "Check_money", Checkmoney )

hook.Add ("OnNPCKilled", "Hai", NPCkilled) [/LUA]

Now, if i try this code it says it can't perform arithmetic on string values. If i delete the quote to make it non-string, the NWint commands wont work because it expected strings.
I just dont see any options here. Anyone knows how to do this either another way, or how im supposed to do it with NWints

[NullPoint]

The arguments to OnNPCKilled are NPC, killer [b]Weapon[/b], you are using the last argument as ply, where you should be using the second (killer).

[editline]08:05AM[/editline]

[b][url=wiki.garrysmod.com/?title=Gamemode.OnNPCKilled]Gamemode.OnNPCKilled [img]http://wiki.garrysmod.com/favicon.ico[/img][/url][/b]

[Averice]

[lua]
hook.Add("OnNPCKilled", "MoneyUp", function(npc,killer,wep)
if not( killer:IsPlayer() ) then return end;
local mon = killer:GetNWInt("money", 0)
killer:SetNWInt("money", mon+10)
end)

concommand.Add("CheckMoney", function(p)
if( p:GetNWInt("money", 0) == 0 ) then
p:PrintMessage(3, "You have no money, Nubcaek");
else
p:PrintMessage(3, "Money: $"..p:GetNWInt("money", 0))
end
end)
[/lua]

[Entoros]

[url=http://entoros.pastebin.com/f2e88e84a]Here's a money system[/url] I made a while back as an example that you can use as a reference. It includes giving and retrieving money from the player and a SQL database.

[DocDoomsday]

ply:SetNWInt( "money", "money" + 10 )

to

ply:SetNWInt("money", ply:GetNWInt("money") + 10 )

Just got done with a gamemode that uses money alot :P