Detect if the value exists or not

Help and Feedback Scripting Support
#1

Hello, developers!

I am trying to detect if the value exists or not.

Script 
local Players = game:GetService("Players")
local Part = script.Parent
local RunService = game:GetService("RunService")

RunService.Heartbeat:Connect(function()
	for i, plr in ipairs(Players:GetPlayers()) do
		local char = plr.Character
		local humanoid = char:FindFirstChildOfClass("Humanoid")
		local rootpart = char:FindFirstChild("HumanoidRootPart")
		local dist = (Part.Position - rootpart.Position).Magnitude
		if dist < 75 then
			if char:WaitForChild("LightOn") then
				if humanoid.Health > 0 then
					task.wait(0.5)
					humanoid:TakeDamage(1)
				end
			end
		end
	end
end)
#2

I don’t understand what you mean. Please provide more context.

#3

Hey, it would be helpful if you included which value you wanted to detect. but this can be done universally with the following steps

value = (whatever you want to set it as)
if value ~= nil then
 -- run the code if the value is not nothing
end
#4 
local value= parent:FindFirstChild("Value name")
if value  then 
--script
end
#5

find first child would return an error if the value wasn’t there, “index nil with find first child”, no?
Also i’m 70% sure they want something numeric, correct me if i’m wrong though.

#6

he wants an instance right?
find first child will return nil if the instance isnt there

#7

Ah okay! thanks for the correction

#8

The script won’t detect the value.

local Players = game:GetService("Players")
local Part = script.Parent
local RunService = game:GetService("RunService")

RunService.Heartbeat:Connect(function()
	for i, plr in ipairs(Players:GetPlayers()) do
		local char = plr.Character
		local humanoid = char:FindFirstChildOfClass("Humanoid")
		local rootpart = char:FindFirstChild("HumanoidRootPart")
		local dist = (Part.Position - rootpart.Position).Magnitude
		local lighton = char:FindFirstChild("LightOn")
		if dist < 10 then
			if lighton ~= nil then
				if humanoid.Health > 0 then
					task.wait(0.5)
					humanoid:TakeDamage(1)
				end
			end
		end
	end
end)
#9

Which value are you trying to detect?

#10

The boolvalue, which is created by a script.

#11

Your checking if the instance exists, not if the value is true or false I think. Try this:

local lighton = char:FindFirstChild("LightOn").Value
		if dist < 10 then
			if lighton == true/false then
#12

The code you provided doesn’t work.

#13

Did you change it to your desired value or did you leave the “true/false” as it was?

Are you recieving any output in the console?

#14 
local Players = game:GetService("Players")
local Part = script.Parent
local RunService = game:GetService("RunService")

RunService.Heartbeat:Connect(function()
	for i, plr in ipairs(Players:GetPlayers()) do
		local char = plr.Character
		local humanoid = char:FindFirstChildOfClass("Humanoid")
		local rootpart = char:FindFirstChild("HumanoidRootPart")
		local dist = (Part.Position - rootpart.Position).Magnitude
		local lighton = char:FindFirstChild("LightOn")
		if dist < 75 then
			if lighton then
				if lighton.Value then
					if humanoid.Health > 0 then
						task.wait(0.5)
						humanoid:TakeDamage(1)
					end
				end
			end
		end
	end
end)
1 Like
#15

Do not use WaitForChild inside a Heartbeat connection, this yields code and is unnecessary considering the code is executed very often(multiple times within a second, in a loop-like manner). Also it may cause a pointless infinite yield, in general if you don’t plan to disconnect a connection afterwards, it’s good to avoid such yields. Here’s what you can do instead:

local RunService = game:GetService("RunService")
local Part = script.Parent 

local function damagePlayer(player: Player): ()
	local c = plr.Character
	if not c then return end
	local humanoid = c:FindFirstChildOfClass("Humanoid")
	local root = c:FindFirstChild("HumanoidRootPart")
	if not root then return end
	local dist = (Part.Position - root.Position).Magnitude
	if dist >= 75 then return end
	local val = c:FindFirstChild("LightOn")
	if not val then return end --perhaps if not val or not val.Value?
	if not humanoid or humanoid.Health <= 0 then return end
	task.wait(0.5)
	humanoid:TakeDamage(1)
end

RunService.Heartbeat:Connect(function()
	for _, player in pairs(game.Players:GetPlayers()) do 
		damagePlayer(player) 
	end
end)
#16

Checking bool value isn’t the same as checking a normal bool datatypes, you’re checking if it has the value, not if it’s true or false

local Players = game:GetService("Players")
local Part = script.Parent
local RunService = game:GetService("RunService")

RunService.Heartbeat:Connect(function()
	for i, plr in ipairs(Players:GetPlayers()) do
		local char = plr.Character
		local humanoid = char:FindFirstChildOfClass("Humanoid")
		local rootpart = char:FindFirstChild("HumanoidRootPart")
		local dist = (Part.Position - rootpart.Position).Magnitude
		local lighton = char:FindFirstChild("LightOn")
		if dist < 75 then
			if lighton and lighton.Value == true then --if there's lighton and and lighton is true or false
				if humanoid.Health > 0 then
					task.wait(0.5)
					humanoid:TakeDamage(1)
				end
			end
		end
	end
end)