getcallbackmember / getcallbackvalue

Gets the value assigned to an object callback property.

Syntax

getcallbackmember(object: Object, property: string, returnRaw?: boolean) -> any?
getcallbackvalue(object: Object, property: string, returnRaw?: boolean) -> any? -- alias

Parameters

Parameter	Type	Description
`object`	`Object`	The object, including an `Instance`
`property`	`string`	The callback property name
`returnRaw`	`boolean?`	Return a non-function callback object instead of filtering it to nil

Returns

Type	Description
`any?`	The callback value, or nil when no callback is assigned

getcallbackvalue reads async callback properties such as BindableFunction.OnInvoke that are normally exposed as write-only. By default, values that are not functions are returned as nil; pass true to retrieve the raw callback object.

The canonical function name is getcallbackmember; getcallbackvalue is an alias.

Example

-- Create a BindableFunction
local bindable = Instance.new("BindableFunction")
bindable.OnInvoke = function(arg)
    return arg * 2
end

-- Get the callback
local callback = getcallbackvalue(bindable, "OnInvoke")
if callback then
    print(callback(5)) -- 10
end

Inspecting Remote Callbacks

-- Find RemoteFunction callbacks
for _, obj in ipairs(game:GetDescendants()) do
    if obj:IsA("RemoteFunction") then
        local callback = getcallbackvalue(obj, "OnClientInvoke")
        if callback then
            print("Found callback on:", obj:GetFullName())
        end
    end
end

Notes

Common callback properties include OnInvoke, OnClientInvoke, and OnServerInvoke
Returns nil if no callback is set