GetPropertyChangedSignal
This method returns an event that behaves exactly like the Changed event, except that the event only fires when the given property changes. It’s generally a good idea to use this method instead of a connection to Changed with a function that checks the property name. Subsequent calls to this method on the same object with the same property name return the same event.
print(object:GetPropertyChangedSignal("Name") == object:GetPropertyChangedSignal("Name")) --> always true
ValueBase objects, such as IntValue and StringValue, use a modified Changed event that fires with the contents of the Value property. As such, this method provides a way to detect changes in other properties of those objects. For example, to detect changes in the Name property of an IntValue, use IntValue:GetPropertyChangedSignal("Name"):Connect(someFunc) since the Changed event of IntValue objects only detect changes on the Value property.
Parameters
| Name | Type | Default | Description |
|---|---|---|---|
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Returns
| Return Type | Summary |
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Code Samples
Changed and GetPropertyChangedSignal
This code sample demonstrates the equivalence of the Changed event and event returned by GetPropertyChangedSignal.
local part = Instance.new("Part")
local function onBrickColorChanged()
print("My color is now " .. part.BrickColor.Name)
end
-- Manual detection of a property change
local function onChanged(property)
if property == "BrickColor" then
onBrickColorChanged()
end
end
-- Connect both events
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")
Old-to-New Values with Changed
This code sample demonstrates how to save a value before a changed event fires on it in order to get more information about a change.
local part = Instance.new("Part")
-- Save the current state
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)
-- Make some changes
part.BrickColor = BrickColor.new("Really red")
part.BrickColor = BrickColor.new("Really blue")