NSNumber and NSTimeInterval

Question

I am trying to get the system time in milliseconds. For this, I stated:

NSNumber *createdTimeInMilliSec; //in class declaration 

and in one of my instance functions, I do:

  self.createdTimeInMilliSec= ([NSDate timeIntervalSinceReferenceDate]*1000); //ERROR: incompatible type for argument 1 of 'setCreatedTimeInMilliSec:' 

timeIntervalSinceReferenceDate returns to NSTimeInterval , so how do I convert it to NSNumber ? Or what am I doing wrong?

Answer 1

NSTimeInterval is printed as follows: typedef double NSTimeInterval; .

To create an NSNumber with, use:

 NSNumber *n = [NSNumber numberWithDouble:yourTimeIntervalValue]; 

Answer 2

I'm not sure if this is clear from the other answers, but NSTimeInterval is actually just a double type. You can get an NSNumber from it by running [NSNumber numberWithDouble:timeInterval] or even more concisely @(timeInterval) .

Answer 3

NSTimeInterval is a typedef for double. Therefore, use the convenience constructor NSNumber numberWithDouble: as follows:

 self.createdTimeInMilliSec= [NSNumber numberWithDouble:([NSDate timeIntervalSinceReferenceDate]*1000)]; 

Answer 4

Since NSTimeInterval is double, you can do

 NSNumber *myNumber = [NSNumber numberWithDouble: myTimeInterval];