iOS NSDate
使用NSTime实现倒计时功能
- (void)timerFireMethod:(NSTimer*)theTimer
{
//NSDateFormatter *dateformatter = [[[NSDateFormatter alloc]init] autorelease];//定义NSDateFormatter用来显示格式
//[dateformatter setDateFormat:@"yyyy MM dd hh mm ss"];//设定格式
NSCalendar *cal = [NSCalendar currentCalendar];//定义一个NSCalendar对象
NSDateComponents *shibo = [[NSDateComponents alloc] init];//初始化目标时间（好像是世博会的日期）
[shibo setYear:2012];
[shibo setMonth:6];
[shibo setDay:1];
[shibo setHour:8];
[shibo setMinute:0];
[shibo setSecond:0];
NSDate *todate = [cal dateFromComponents:shibo];//把目标时间装载入date
[shibo release];
// NSString *ssss = [dateformatter stringFromDate:dd];
// NSLog([NSString stringWithFormat:@"shibo shi:%@",ssss]);
NSDate *today = [NSDate date];//得到当前时间
// NSString *sss = [dateformatter stringFromDate:today];
// NSLog([NSString stringWithFormat:@"xianzai shi:%@",sss]);
//用来得到具体的时差
unsigned int unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
NSDateComponents *d = [cal components:unitFlags fromDate:today toDate:todate options:0];
NSString *result = [NSString stringWithFormat:@"%d年%d月%d日%d时%d分%d秒",[d year],[d month], [d day], [d hour], [d minute], [d second]];
NSLog(@"%@",result);
}
在 初始化方法中调用[NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(timerFireMethod:) userInfo:nil repeats:YES];即可
NSData年、月、星期、日、时、分、秒和毫秒获取及NSDataToNSString方法
NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDate *now;
NSDateComponents *comps = [[NSDateComponents alloc] init];
NSInteger unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSWeekdayCalendarUnit |
NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
now=[NSDate date];
comps = [calendar components:unitFlags fromDate:now];
int year=[comps year];
int week = [comps weekday];
int month = [comps month];
int day = [comps day];
int hour = [comps hour];
int min = [comps minute];
int sec = [comps second];
NSLog(@"%d-%d-%d %d:%d:%d",year,month,day,hour,min,sec);
NSMutableDictionary *dictionary =[NSMutableDictionary dictionaryWithCapacity:2];
[dictionary setValue:path forKey:@"photo_path"];
NSDate *date = [NSDate date];
NSTimeZone *zone = [NSTimeZone systemTimeZone];
NSInteger interval = [zone secondsFromGMTForDate: date];
NSDate *localeDate = [date dateByAddingTimeInterval: interval];
NSLog(@"%@", localeDate);
NSLog(@"%@",[self NSDateToNSTring:[NSDate date]]);//返回的是GTM时间
NSLog(@"%@",[self NSDateToNSTring:localeDate]);//返回的是北京时间
-(NSString *)NSDateToNSTring:(NSDate *)nsDate
{
//NSString *string = [nsDate descriptionWithCalendarFormat:@"%Y/%m/%d %H:%M:%S" timeZone:nil locale:nil]; 此方法为是有API如果要上传APP不要使用
NSDateFormatter *fmt = [[[NSDateFormatter alloc] init] autorelease];
// [fmt setDateFormat:@"hh:mm:ss:SSS"];
[fmt setDateFormat:@"yyyy/MM/dd hh:mm:ss:SSS"];
NSString *string=[fmt stringFromDate:nsDate];
return string;
}
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDate *date = [NSDate date];
NSDateComponents *dateComponents = [gregorian components:(NSHourCalendarUnit|NSMinuteCalendarUnit|NSSecondCalendarUnit) fromDate:date];
[gregorian release];
NSLog(@"%02i:%02i:%02i",[dateComponents hour],[dateComponents minute],[dateComponents second]);
CFGregorianDate currentDate = CFAbsoluteTimeGetGregorianDate(CFAbsoluteTimeGetCurrent(), CFTimeZoneCopySystem());
NSLog(@"%04ld-%02i-%02i %02i:%02i:%02.0f", currentDate.year,currentDate.month,currentDate.day,currentDate.hour,currentDate.minute,currentDate.second);
iphone获取1970年以来的毫秒数
// NSTimeInterval返回的是double类型，输出会显示为10位整数加小数点加一些其他值
// 如果想转成int型，必须转成long long型才够大。
NSTimeInterval time = [[NSDate date] timeIntervalSince1970];
long long dTime = [[NSNumber numberWithDouble:time] longLongValue]; // 将double转为long long型
NSString *curTime = [NSString stringWithFormat:@"%llu",dTime]; // 输出long long型
NSLog(@"%@",curTime);
iOS 应用里获取日期间隔的方法
//NSDate，类似java里面的Date对象，是对从1970-1-1毫秒数的封装，可记录时间;
//NSDateFormatter，类似java中的DateFormat相关的api，用于日期对象的格式化或者字符串解析为日期对象。
//首先，创建一个日期格式化对象：
NSDateFormatter *dateFormatter=[[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm"];
//然后，创建了两个日期对象：
NSDate *date1=[dateFormatter dateFromString:@"2010-3-3 11:00"];
NSDate *date2=[dateFormatter dateFromString:@"2010-3-4 12:00"];
//创建日期对象，是通过字符串解析的。
//然后取两个日期对象的时间间隔：
NSTimeInterval time=[date2 timeIntervalSinceDate:date1];
//这里的NSTimeInterval 并不是对象，是基本型，其实是double类型，是由c定义的:
typedef double NSTimeInterval;
//再然后，把间隔的秒数折算成天数和小时数：
int days=((int)time)/(3600*24);
int hours=((int)time)%(3600*24)/3600;
NSString *dateContent=[[NSString alloc] initWithFormat:@"%i天%i小时",days,hours];
NSLog(@"%@",dateContent);
ios中NSString与NSDate互转
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
NSTimeZone *timeZone = [NSTimeZone localTimeZone];
[formatter setTimeZone:timeZone];
[formatter setDateFormat : @"M/d/yyyy h:m a"];
NSString *stringTime = @"12/5/2011 3:4 am";
NSDate *dateTime = [formatter dateFromString:stringTime];
NSLog(@"%@", dateTime);//打印2011-12-04 19:04:00 +0000，这里+0000表示时区
NSDate *dateNow = [NSDate date];
NSLog(@"%@", dateNow);//打印2011-08-17 08:26:57 +0000，这里+0000表示时区
[formatter setDateFormat : @"yyyy年M月d日H点m分"];
NSLog(@"%@", [formatter stringFromDate:dateNow]);//打印2011年8月17日16点26分
NSDateFormatter setDateFormat 自定义日期/时间格式
NSDateFormatter *dateFormatter =[[NSDateFormatter alloc] init];
// NSString *tzStr = [[date description] substringFromIndex:20];
// NSLog(@"\ndate\t:[%@]\ntime zone\t:[%@]", [date description], tzStr);
// [dateFormatter setTimeZone:tzStr];
[dateFormatter setDateFormat:@"MM d','h:m a"];
// [dateFormatter setDateStyle:kCFDateFormatterMediumStyle];
// [dateFormatter setTimeStyle:kCFDateFormatterShortStyle];
// [NSLog(@"Local time zone [%@'", [dateFormatter timeZone]);
NSString *dateStr = [dateFormatter stringFromDate:[NSDate date]];
NSLog(@"==========%@",dateStr);
NSDateFormatter
格式化日期字符串，copy一份常用参数：
a: AM/PM (上午/下午)
A: 0~86399999 (一天的第A微秒)
c/cc: 1~7 (一周的第一天, 周天为1)
ccc: Sun/Mon/Tue/Wed/Thu/Fri/Sat (星期几简写)
cccc: Sunday/Monday/Tuesday/Wednesday/Thursday/Friday/Saturday (星期几全拼)
d: 1~31 (月份的第几天, 带0)
D: 1~366 (年份的第几天,带0)
e: 1~7 (一周的第几天, 带0)
E~EEE: Sun/Mon/Tue/Wed/Thu/Fri/Sat (星期几简写)
EEEE: Sunday/Monday/Tuesday/Wednesday/Thursday/Friday/Saturday (星期几全拼)
F: 1~5 (每月的第几周, 一周的第一天为周一)
g: Julian Day Number (number of days since 4713 BC January 1) 未知
G~GGG: BC/AD (Era Designator Abbreviated) 未知
GGGG: Before Christ/Anno Domini 未知
h: 1~12 (0 padded Hour (12hr)) 带0的时, 12小时制
H: 0~23 (0 padded Hour (24hr)) 带0的时, 24小时制
k: 1~24 (0 padded Hour (24hr) 带0的时, 24小时制
K: 0~11 (0 padded Hour (12hr)) 带0的时, 12小时制
L/LL: 1~12 (0 padded Month) 第几月
LLL: Jan/Feb/Mar/Apr/May/Jun/Jul/Aug/Sep/Oct/Nov/Dec 月份简写
LLLL: January/February/March/April/May/June/July/August/September/October/November/December 月份全称
m: 0~59 (0 padded Minute) 分钟
M/MM: 1~12 (0 padded Month) 第几月
MMM: Jan/Feb/Mar/Apr/May/Jun/Jul/Aug/Sep/Oct/Nov/Dec
MMMM: January/February/March/April/May/June/July/August/September/October/November/December
q/qq: 1~4 (0 padded Quarter) 第几季度
qqq: Q1/Q2/Q3/Q4 季度简写
qqqq: 1st quarter/2nd quarter/3rd quarter/4th quarter 季度全拼
Q/QQ: 1~4 (0 padded Quarter) 同小写
QQQ: Q1/Q2/Q3/Q4 同小写
QQQQ: 1st quarter/2nd quarter/3rd quarter/4th quarter 同小写
s: 0~59 (0 padded Second) 秒数
S: (rounded Sub-Second) 未知
u: (0 padded Year) 未知
v~vvv: (General GMT Timezone Abbreviation) 常规GMT时区的编写
vvvv: (General GMT Timezone Name) 常规GMT时区的名称
w: 1~53 (0 padded Week of Year, 1st day of week = Sunday, NB: 1st week of year starts from the last Sunday of last year) 一年的第几周, 一周的开始为周日,第一周从去年的最后一个周日起算
W: 1~5 (0 padded Week of Month, 1st day of week = Sunday) 一个月的第几周
y/yyyy: (Full Year) 完整的年份
yy/yyy: (2 Digits Year) 2个数字的年份
Y/YYYY: (Full Year, starting from the Sunday of the 1st week of year) 这个年份未知干嘛用的
YY/YYY: (2 Digits Year, starting from the Sunday of the 1st week of year) 这个年份未知干嘛用的
z~zzz: (Specific GMT Timezone Abbreviation) 指定GMT时区的编写
zzzz: (Specific GMT Timezone Name) Z: +0000 (RFC 822 Timezone) 指定GMT时区的名称
实例：
http://blog.sina.com.cn/s/blog_60b45f230100i0r9.html
NSDateFormatter * dateFormatter = [[[NSDateFormatter alloc] init]autorelease];
[dateFormatter setAMSymbol:@"AM"];
[dateFormatter setPMSymbol:@"PM"];
[dateFormatter setDateFormat:@"dd/MM/yyyy hh:mmaaa"];
NSDate *date = [NSDate date];
NSString * s = [dateFormatter stringFromDate:date];
显示效果为：10/05/2010 03:49PM
下面附上几个格式：这个是从Cocoachina上来的。呵呵。
yyyy:MM:dd G 'at' HH:mm:ss zzz 1996.07.10 AD at 15:08:56 PDT
EEE, MMM d, "yy Wed,july 10, '99
h:mm a 12:08 PM
hh 'o"clock' a,zzzz 12 o'clock PM, Pacific Daylight Time
K:mm a, z 0:00 PM, PST
yyyyy,MMMM.dd GGG hh:mm aaa 01996.july.10 AD 12:08 PM
下面是得到当前的年，月，日，时，分，秒。
NSCalendar *cal = [NSCalendar currentCalendar];
unsigned int unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
NSDateComponents *dd = [cal components:unitFlags fromDate:date];
int y = [dd year];
int m = [dd month];
int d = [dd day];
int h = [dd hour];
int m = [dd minute];
int s = [dd second];
NSDate获取当前时区的时间
[NSDate date]获取的是GMT时间，要想获得某个时区的时间，以下代码可以解决这个问题
NSDate *date = [NSDate date];
NSTimeZone *zone = [NSTimeZone systemTimeZone];
NSInteger interval = [zone secondsFromGMTForDate: date];
NSDate *localeDate = [date dateByAddingTimeInterval: interval];
NSLog(@"%@", localeDate);