unity3d - How to get device token of device in Unity 5? -

i tring device token , dont want use update function.

right using following function:

if (!tokensent) {     token =unityengine.ios.notificationservices.devicetoken;     if (token != null) {         // send token provider         print ("my device token");         hextoken= "%" + system.bitconverter.tostring(token).replace('-', '%');         tokensent = true;     } }