取得当前的年月日，当前的时分秒获得，周几和星期几获得
NSDate*date = [NSDate date];
NSCalendar*calendar = [NSCalendar currentCalendar];
NSDateComponents*comps;
// 年月日获得
comps =[calendar components:(NSYearCalendarUnit | NSMonthCalendarUnit |NSDayCalendarUnit)
fromDate:date];
NSIntegeryear = [comps year];
NSIntegermonth = [comps month];
NSIntegerday = [comps day];
NSLog(@"year:%d month: %d, day: %d", year, month, day);
//当前的时分秒获得
comps =[calendar components:(NSHourCalendarUnit | NSMinuteCalendarUnit |NSSecondCalendarUnit)
fromDate:date];
NSIntegerhour = [comps hour];
NSIntegerminute = [comps minute];
NSIntegersecond = [comps second];
NSLog(@"hour:%d minute: %d second: %d", hour, minute, second);
// 周几和星期几获得
comps =[calendar components:(NSWeekCalendarUnit | NSWeekdayCalendarUnit |NSWeekdayOrdinalCalendarUnit)
fromDate:date];
NSInteger week = [comps week]; // 今年的第几周
NSIntegerweekday = [comps weekday]; // 星期几（注意，周日是“1”，周一是“2”。。。。）
NSIntegerweekdayOrdinal = [comps weekdayOrdinal]; // 这个月的第几周
NSLog(@"week:%d weekday: %d weekday ordinal: %d", week, weekday, weekdayOrdinal);
NSDateFormatter*dateFormatter = [[NSDateFormatter alloc]init];
if(dateSwitch.on)
[dateFormattersetDateFormat:@"dd-MMM-yyy,hh:mm:ss"];
else
[dateFormatter setDateFormat:@"hh:mm:ss"];
labelTime.text = [dateFormatter stringFromDate:[NSDatedate]];
labelTime.font = [UIFontsystemFontOfSize:fontSlider.value];
[dateFormatter release];
//后台时间戳转化为yyyy年MM月dd日
const long long dateTimeLong =[value longLongValue]/1000;
NSDate *dateTime = [[NSDate alloc] initWithTimeIntervalSince1970:dateTimeLong];
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setTimeStyle:NSDateFormatterNoStyle];
[formatter setDateStyle:NSDateFormatterMediumStyle];
NSLocale *formatterLocal = [[NSLocale alloc] initWithLocaleIdentifier:@"en_us"];
[formatter setLocale:formatterLocal];
[formatter setDateFormat:@"yyyy年MM月dd日"];
NSDate *new = [NSDate dateWithTimeInterval:0 sinceDate:dateTime];
NSString *dateString = [formatter stringFromDate:new];
转载于:https://www.cnblogs.com/KingQiangzi/p/4274190.html
