c# - Determining which flags are missing from enum -

lets have enum below:

[flags] public enum notifytype {      none = 0,     window = 1 << 0,     sound = 1 << 1,     flash = 1 << 2,     mobilesound = 1 << 3,     mobilepush = 1 << 4 } 

considering 2 enums:

var myenums = window | sound | flash;   //var possibleupdate = window | mobilepush;  void updatemyenums(notifytype possibleupdate) {     //does myenums contain flags in 'possibleupdate'?  if not add     //the missing flags myenums  } 

how possible determine myenums variable not contain notifytype.mobilepush value in comparison possibleupdate? have test each flag in possibleupdate against myenums?

i using c# on .net 4.0

there no need figure out 1 missing, need bit-wise or between myenums , possibleupdate , assign value back.

//does myenums contain flags in 'possibleupdate'?   if (myenums & possibleupdate != possibleupdate)     //if not add missing flags myenums     myenums = myenums | possibleupdate;