Learn
Engine Class
Object
Not Creatable
Not Replicated

Summary
Properties
className:string
Deprecated
Methods
IsA(className: string):boolean
isA(className: string):boolean
Deprecated
Events

API Reference
Properties
ClassName
Read Only
Not Replicated
Read Parallel
Object.ClassName:string

className
Deprecated

Methods
GetPropertyChangedSignal
Object:GetPropertyChangedSignal(property:string):RBXScriptSignal
Parameters
property:string
Code Samples
Old-to-New Values with Changed
local part = Instance.new("Part")
local currentColor = part.BrickColor
local function onBrickColorChanged()
local newColor = part.BrickColor
print("Color changed from", currentColor.Name, "to", newColor.Name)
currentColor = newColor
end
part:GetPropertyChangedSignal("BrickColor"):Connect(onBrickColorChanged)
part.BrickColor = BrickColor.new("Really red")
part.BrickColor = BrickColor.new("Really blue")
Changed and GetPropertyChangedSignal
local part = Instance.new("Part")
local function onBrickColorChanged()
print("My color is now " .. part.BrickColor.Name)
end
local function onChanged(property)
if property == "BrickColor" then
onBrickColorChanged()
end
end
part:GetPropertyChangedSignal("BrickColor"):Connect(onBrickColorChanged)
part.Changed:Connect(onChanged)
-- Trigger some changes (because we connected twice,
-- both of these will cause two calls to onBrickColorChanged)
part.BrickColor = BrickColor.new("Really red")
part.BrickColor = BrickColor.new("Institutional white")

IsA
Write Parallel
Object:IsA(className:string):boolean
Parameters
className:string
Returns
Code Samples
Instance:IsA()
local Workspace = game:GetService("Workspace")
print(Workspace:IsA("Workspace")) -- true
print(Workspace:IsA("BasePart")) -- false
print(Workspace:IsA("Instance")) -- true

isA
Deprecated

Events
Changed
Object.Changed(property:string):RBXScriptSignal
Parameters
property:string
Code Samples
Changed Event
-- Demonstrate the Changed event by creating a Part
local part = Instance.new("Part")
part.Changed:Connect(print)
-- This fires Changed with "Transparency"
part.Transparency = 0.5
-- Similarly, this fires Changed with "Number"
part.Name = "SomePart"
-- Since changing BrickColor will also change other
-- properties at the same time, this line fires Changed
-- with "BrickColor", "Color3" and "Color3uint16".
part.BrickColor = BrickColor.Red()
-- A NumberValue holds a double-precision floating-point number
local vNumber = Instance.new("NumberValue")
vNumber.Changed:Connect(print)
-- This fires Changed with 123.456 (not "Value")
vNumber.Value = 123.456
-- This does not fire Changed
vNumber.Name = "SomeNumber"
-- A StringValue stores one string
local vString = Instance.new("StringValue")
vString.Changed:Connect(print)
-- This fires Changed with "Hello" (not "Value")
vString.Value = "Hello"
Change Detector
local object = script.Parent
local function onChanged(property)
-- Get the current value of the property
local value = object[property]
-- Print a message saying what changed
print(object:GetFullName() .. "." .. property .. " (" .. typeof(value) .. ") changed to " .. tostring(value))
end
object.Changed:Connect(onChanged)
-- Trigger a simple change in the object (add an underscore to the name)
object.Name = "_" .. object.Name

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