获得年月日 NSDate

- (NSDate *)dateWithYMD

{

//    1

    NSTimeZone* GTMzone = [NSTimeZone timeZoneForSecondsFromGMT:0];

    NSDateFormatter *fmt = [[NSDateFormatter alloc] init];

    [fmt setTimeZone:GTMzone];

    fmt.dateFormat = @"yyyy-MM-dd";

    NSString *selfStr = [fmt stringFromDate:self];

    return [fmt dateFromString:selfStr];

//    2

    NSTimeZone* GTMzone = [NSTimeZone timeZoneForSecondsFromGMT:0];

    NSCalendar *calendar = [NSCalendar currentCalendar];

    calendar.timeZone = GTMzone;

    NSDateComponents *dateComponents = [calendar components:NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit fromDate:[NSDate date]];

    return [calendar dateFromComponents:dateComponents];

}