这两个陈述有什么区别
NSDate *today = [NSDate date]; NSDate *tomarow = [today dateByAddingTimeInterval:60*60*24]; NSDate *nextday = [NSDate dateWithTimeInterval:60*60*24 sinceDate:today];
objective-c nsdate nstimeinterval
nsdate ×1
nstimeinterval ×1
objective-c ×1