Getting the parameters of an event only once

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#1

Hey, i want to get the parameters of an event only once, i need that for an callback system:
Ive tried stuff like this:

local connection
		local res = ""
		
		connection = Callback.OnServerEvent:Connect(function(sender, res)
			
			print(res)
			
			connection:Disconnect()
		end)
		
		print(res)

		Callback:Destroy()

(res will not update)

#2

You never set res to what res is in the event. You only printed it.