That will not provide an accurate reading of the current. In almost all low cost LED drivers ( and some of the more expensive ones ) the output is far from steady smoothed DC. A driver with an output labelled 12 Vdc (eff) is effectively 12 volts but in reality could be as bad as 36 volt pulses with gaps between such that the average is 12 volts. This has the advantage that the LED elements appear to be three times as bright as they would be on a steady smoothed DC supply.
Rubbish.