ios (oc) 比较2个时间的差值

+ (void)pleaseInsertStarTimeo:(NSString *)time1 andInsertEndTime:(NSString *)time2{
    // 1.将时间转换为date
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    formatter.dateFormat = @"yyyy-MM-dd HH:mm:ss";
    NSDate *date1 = [formatter dateFromString:time1];
    NSDate *date2 = [formatter dateFromString:time2];
    // 2.创建日历
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSCalendarUnit type = NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay | NSCalendarUnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond;
    // 3.利用日历对象比较两个时间的差值
    NSDateComponents *cmps = [calendar components:type fromDate:date1 toDate:date2 options:0];
    // 4.输出结果
    Log_c(@"两个时间差 = %ld年 %ld月 %ld日 %ld时 %ld分 %ld秒", cmps.year, cmps.month, cmps.day, cmps.hour, cmps.minute, cmps.second);
}

注：参数的time1 time2 的取值如下

NSDate *senddate = [NSDate date];

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

[dateformatter setDateFormat:@"YYYY-MM-dd HH:mm:ss"];

NSString*time = [dateformatter stringFromDate:senddate];