NSDate简单介绍

NSDate简单介绍

一:NSDate是一个日期\时间方面的类,主要用来创建\获取时间

1.NSDate对象的创建:

date 创建一个当前系统日期和时间的对象

dateWithTimeIntervalSinceNow: 创建距离当前时间戳的对象

dateWithTimeInterval:sinceDate: 创建距离日期和时间对象的时间戳的对象

dateWithTimeIntervalSince1970: 创建距离1970年的时间戳对象

这里简单阐述下时间戳:时间戳的字面意思就是唯一的标识某一刻的时间,比如:2016年4月27日17点54分30秒,这就是我写这句话的时间戳

简单来说:就是从指定时间开始的那一秒数(楼主自己的理解)

2.类方法:

distantFuture 获取很久以后的日期对象

distantPast 获取很久以前的日期对象

3.日期时间比较:

isEqualToDate: 比较日期时间是否相等

earlierDate: 较早的那个日期时间

laterDate: 较晚的那个日期时间

compare: 时间先后

4.获取时间戳

timeIntervalSinceDate: 获取到指定日期时间的时间戳

timeIntervalSinceNow: 获取到现在的时间戳

timeIntervalSince1970: 获取从1970年到指定日期的时间戳

5.在日期时间对象上增加时间戳:

dateByAddingTimeInterval:返回新NSDate对象

二.代码

1.创建日期:

 1 //创建一个日期时间对象
 2         NSDate *nowDate = [NSDate date];
 3         //                     时区
 4         //2015-07-20 08:08:40 +0000
 5         //          + 8
 6         NSLog(@"date = %@",nowDate);
 7         //2)日期时间的格式化显示
 8         // NSDateFormatter 类完成
 9         NSDateFormatter *formatter = [NSDateFormatter new];
10         // 指定了显示的格式
11         // formatter.dateFormat 可以赋值一个字符串,字符串就是我们要显示的格
12         formatter.dateFormat = @"yyyy年MM月dd日 HH时mm分ss秒";
13         /*
14          
15          y 表示年
16          yyyy  表示显示4位的年  2015
17          MM    表示月份(两位M表示不足两位补0)
18          dd    表示天数
19          
20          HH    以24小时制显示 小时
21          hh 以12小时制小时
22          mm    显示分钟
23          ss    显示秒数
24          */
25         //用指定的格式对我们的 nowDate进行格式化
26         // 把date 转换为字符串
27         // 按照我们指定的格式进行转换
28         NSString *dateStr = [formatter stringFromDate:nowDate];
29         NSLog(@"dataStr = %@",dateStr);
30         
31         //计算日期
32         // 当前日期
33         NSDate *date = [NSDate date];
34         NSTimeInterval time = 60*60*24;  //24小时的秒数
35         //明天的此刻
36         NSDate *mt = [date dateByAddingTimeInterval:time];
37         NSDateFormatter *formatter0 = [NSDateFormatter new];
38         // 指定了显示的格式
39         // formatter.dateFormat 可以赋值一个字符串,字符串就是我们要显示的格式
40         formatter0.dateFormat = @"yyyy年MM月dd日 HH时mm分ss秒";
41         NSString *timeStr = [formatter stringFromDate:mt];
42         NSLog(@"timeStr = %@",timeStr);
43         NSTimeInterval time1 = 60*60*24;  //24小时的秒数
44         //昨天的现在
45         NSDate *date1 = [NSDate dateWithTimeIntervalSinceNow:time1];
46         NSDateFormatter *formatter1 = [NSDateFormatter new];
47         // 指定了显示的格式
48         // formatter.dateFormat 可以赋值一个字符串,字符串就是我们要显示的格式
49         formatter1.dateFormat = @"yyyy年MM月dd日 HH时mm分ss秒";
50         NSString *timeStr1 = [formatter stringFromDate:date1];
51         NSLog(@"timeStr = %@",timeStr1);
52         
53 //        例:
54         //刚才返回的 2015年07月19日 16时29分16秒  字符串?
55         //假设 我要去获取日期的 年份  月份  天数
56         //NSCalendar 可以帮我们分解日期的每一部分
57         //创建日期时间对象
58         NSCalendar *cal = [NSCalendar currentCalendar];
59         
60         //获取当前日期的每一部分                  要获取的部分                                从哪个日期对象
61         NSDateComponents *coms = [cal components:NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitDay fromDate:[NSDate date]];
62         
63         NSLog(@"------%ld,-----%ld,----%ld",coms.year,coms.month,coms.day);

2.打印结果:

1 2016-04-27 18:16:08.182 NADate[11660:455237] date = 2016-04-27 10:16:08 +0000
2 2016-04-27 18:16:08.183 NADate[11660:455237] dataStr = 2016年04月27日 18时16分08秒
3 2016-04-27 18:16:08.183 NADate[11660:455237] timeStr = 2016年04月28日 18时16分08秒
4 2016-04-27 18:16:08.183 NADate[11660:455237] timeStr = 2016年04月28日 18时16分08秒
5 2016-04-27 18:16:08.184 NADate[11660:455237] ------2016,-----4,----27
6 Program ended with exit code: 0
View Code

 

3.日期格式化:

 1 //
 2 //  main.m
 3 //  NADate
 4 //
 5 //  Created by admin on 16/4/27.
 6 //  Copyright © 2016年 admin. All rights reserved.
 7 //
 8 
 9 #import <Foundation/Foundation.h>
10 
11 int main(int argc, const char * argv[]) {
12     @autoreleasepool {
13         //创建日期时间格式化对象
14         NSDateFormatter *df = [[NSDateFormatter alloc] init];
15         
16         
17         //        查看时区
18         NSArray *arr = [NSTimeZone knownTimeZoneNames];
19         NSLog(@"%@",arr);
20         
21 
22         df.timeZone = [NSTimeZone timeZoneWithName:@"Asia/Chongqing"];
23         
24         //设置格式化内容
25         df.dateFormat = @"yyyy-MM-dd HH:mm:ss";
26         
27         //        把字符串转换成日期对象
28         NSDate *date = [df dateFromString:@"2005-08-30 08:00:00"];
29         NSLog(@"%@",date);
30         //        把日期对象转换成字符串
31         NSDate *nowDate = [NSDate date];
32         NSString *string= [df stringFromDate:nowDate];
33         NSLog(@"%@",string);
34         
35         //创建日历对象
36 //                NSCalendar *calendar1 = [NSCalendar currentCalendar];
37 //                NSCalendar *calendar2 = [NSCalendar calendarWithIdentifier:NSCalendarIdentifierChinese];
38 //                NSLog(@"%@",calendar1.calendarIdentifier);
39 //                NSLog(@"%@",calendar2.calendarIdentifier);
40         
41         //地区标识
42 //                NSArray *arr1 = [NSLocale availableLocaleIdentifiers];
43 //                NSLog(@"%@",arr1);
44         
45         //
46         NSCalendar *cl = [NSCalendar calendarWithIdentifier:NSCalendarIdentifierChinese];
47         //设置地区
48         cl.locale = [NSLocale localeWithLocaleIdentifier:@"zh_CN"];
49         //设置时区
50         cl.timeZone = [NSTimeZone timeZoneWithName:@"Asia/Chongqing"];
51         //设置每周起始
52         cl.firstWeekday = 2;
53         //获取年月日
54         NSDate *now = [NSDate date];
55         NSInteger month,day;
56         //获取年月日的方法(NSCalendar的对象方法)
57         [cl getEra:nil year:nil month:&month day:&day fromDate:now];
58         NSLog(@"%ld月%ld日\n",month,day);

4.打印结果:

  1 2016-04-27 18:26:03.929 NADate[11684:458251] (
  2     "Africa/Abidjan",
  3     "Africa/Accra",
  4     "Africa/Addis_Ababa",
  5     "Africa/Algiers",
  6     "Africa/Asmara",
  7     "Africa/Bamako",
  8     "Africa/Bangui",
  9     "Africa/Banjul",
 10     "Africa/Bissau",
 11     "Africa/Blantyre",
 12     "Africa/Brazzaville",
 13     "Africa/Bujumbura",
 14     "Africa/Cairo",
 15     "Africa/Casablanca",
 16     "Africa/Ceuta",
 17     "Africa/Conakry",
 18     "Africa/Dakar",
 19     "Africa/Dar_es_Salaam",
 20     "Africa/Djibouti",
 21     "Africa/Douala",
 22     "Africa/El_Aaiun",
 23     "Africa/Freetown",
 24     "Africa/Gaborone",
 25     "Africa/Harare",
 26     "Africa/Johannesburg",
 27     "Africa/Juba",
 28     "Africa/Kampala",
 29     "Africa/Khartoum",
 30     "Africa/Kigali",
 31     "Africa/Kinshasa",
 32     "Africa/Lagos",
 33     "Africa/Libreville",
 34     "Africa/Lome",
 35     "Africa/Luanda",
 36     "Africa/Lubumbashi",
 37     "Africa/Lusaka",
 38     "Africa/Malabo",
 39     "Africa/Maputo",
 40     "Africa/Maseru",
 41     "Africa/Mbabane",
 42     "Africa/Mogadishu",
 43     "Africa/Monrovia",
 44     "Africa/Nairobi",
 45     "Africa/Ndjamena",
 46     "Africa/Niamey",
 47     "Africa/Nouakchott",
 48     "Africa/Ouagadougou",
 49     "Africa/Porto-Novo",
 50     "Africa/Sao_Tome",
 51     "Africa/Tripoli",
 52     "Africa/Tunis",
 53     "Africa/Windhoek",
 54     "America/Adak",
 55     "America/Anchorage",
 56     "America/Anguilla",
 57     "America/Antigua",
 58     "America/Araguaina",
 59     "America/Argentina/Buenos_Aires",
 60     "America/Argentina/Catamarca",
 61     "America/Argentina/Cordoba",
 62     "America/Argentina/Jujuy",
 63     "America/Argentina/La_Rioja",
 64     "America/Argentina/Mendoza",
 65     "America/Argentina/Rio_Gallegos",
 66     "America/Argentina/Salta",
 67     "America/Argentina/San_Juan",
 68     "America/Argentina/San_Luis",
 69     "America/Argentina/Tucuman",
 70     "America/Argentina/Ushuaia",
 71     "America/Aruba",
 72     "America/Asuncion",
 73     "America/Atikokan",
 74     "America/Bahia",
 75     "America/Bahia_Banderas",
 76     "America/Barbados",
 77     "America/Belem",
 78     "America/Belize",
 79     "America/Blanc-Sablon",
 80     "America/Boa_Vista",
 81     "America/Bogota",
 82     "America/Boise",
 83     "America/Cambridge_Bay",
 84     "America/Campo_Grande",
 85     "America/Cancun",
 86     "America/Caracas",
 87     "America/Cayenne",
 88     "America/Cayman",
 89     "America/Chicago",
 90     "America/Chihuahua",
 91     "America/Costa_Rica",
 92     "America/Creston",
 93     "America/Cuiaba",
 94     "America/Curacao",
 95     "America/Danmarkshavn",
 96     "America/Dawson",
 97     "America/Dawson_Creek",
 98     "America/Denver",
 99     "America/Detroit",
100     "America/Dominica",
101     "America/Edmonton",
102     "America/Eirunepe",
103     "America/El_Salvador",
104     "America/Fort_Nelson",
105     "America/Fortaleza",
106     "America/Glace_Bay",
107     "America/Godthab",
108     "America/Goose_Bay",
109     "America/Grand_Turk",
110     "America/Grenada",
111     "America/Guadeloupe",
112     "America/Guatemala",
113     "America/Guayaquil",
114     "America/Guyana",
115     "America/Halifax",
116     "America/Havana",
117     "America/Hermosillo",
118     "America/Indiana/Indianapolis",
119     "America/Indiana/Knox",
120     "America/Indiana/Marengo",
121     "America/Indiana/Petersburg",
122     "America/Indiana/Tell_City",
123     "America/Indiana/Vevay",
124     "America/Indiana/Vincennes",
125     "America/Indiana/Winamac",
126     "America/Inuvik",
127     "America/Iqaluit",
128     "America/Jamaica",
129     "America/Juneau",
130     "America/Kentucky/Louisville",
131     "America/Kentucky/Monticello",
132     "America/Kralendijk",
133     "America/La_Paz",
134     "America/Lima",
135     "America/Los_Angeles",
136     "America/Lower_Princes",
137     "America/Maceio",
138     "America/Managua",
139     "America/Manaus",
140     "America/Marigot",
141     "America/Martinique",
142     "America/Matamoros",
143     "America/Mazatlan",
144     "America/Menominee",
145     "America/Merida",
146     "America/Metlakatla",
147     "America/Mexico_City",
148     "America/Miquelon",
149     "America/Moncton",
150     "America/Monterrey",
151     "America/Montevideo",
152     "America/Montreal",
153     "America/Montserrat",
154     "America/Nassau",
155     "America/New_York",
156     "America/Nipigon",
157     "America/Nome",
158     "America/Noronha",
159     "America/North_Dakota/Beulah",
160     "America/North_Dakota/Center",
161     "America/North_Dakota/New_Salem",
162     "America/Ojinaga",
163     "America/Panama",
164     "America/Pangnirtung",
165     "America/Paramaribo",
166     "America/Phoenix",
167     "America/Port-au-Prince",
168     "America/Port_of_Spain",
169     "America/Porto_Velho",
170     "America/Puerto_Rico",
171     "America/Rainy_River",
172     "America/Rankin_Inlet",
173     "America/Recife",
174     "America/Regina",
175     "America/Resolute",
176     "America/Rio_Branco",
177     "America/Santa_Isabel",
178     "America/Santarem",
179     "America/Santiago",
180     "America/Santo_Domingo",
181     "America/Sao_Paulo",
182     "America/Scoresbysund",
183     "America/Shiprock",
184     "America/Sitka",
185     "America/St_Barthelemy",
186     "America/St_Johns",
187     "America/St_Kitts",
188     "America/St_Lucia",
189     "America/St_Thomas",
190     "America/St_Vincent",
191     "America/Swift_Current",
192     "America/Tegucigalpa",
193     "America/Thule",
194     "America/Thunder_Bay",
195     "America/Tijuana",
196     "America/Toronto",
197     "America/Tortola",
198     "America/Vancouver",
199     "America/Whitehorse",
200     "America/Winnipeg",
201     "America/Yakutat",
202     "America/Yellowknife",
203     "Antarctica/Casey",
204     "Antarctica/Davis",
205     "Antarctica/DumontDUrville",
206     "Antarctica/Macquarie",
207     "Antarctica/Mawson",
208     "Antarctica/McMurdo",
209     "Antarctica/Palmer",
210     "Antarctica/Rothera",
211     "Antarctica/South_Pole",
212     "Antarctica/Syowa",
213     "Antarctica/Troll",
214     "Antarctica/Vostok",
215     "Arctic/Longyearbyen",
216     "Asia/Aden",
217     "Asia/Almaty",
218     "Asia/Amman",
219     "Asia/Anadyr",
220     "Asia/Aqtau",
221     "Asia/Aqtobe",
222     "Asia/Ashgabat",
223     "Asia/Baghdad",
224     "Asia/Bahrain",
225     "Asia/Baku",
226     "Asia/Bangkok",
227     "Asia/Beirut",
228     "Asia/Bishkek",
229     "Asia/Brunei",
230     "Asia/Chita",
231     "Asia/Choibalsan",
232     "Asia/Chongqing",
233     "Asia/Colombo",
234     "Asia/Damascus",
235     "Asia/Dhaka",
236     "Asia/Dili",
237     "Asia/Dubai",
238     "Asia/Dushanbe",
239     "Asia/Gaza",
240     "Asia/Harbin",
241     "Asia/Hebron",
242     "Asia/Ho_Chi_Minh",
243     "Asia/Hong_Kong",
244     "Asia/Hovd",
245     "Asia/Irkutsk",
246     "Asia/Jakarta",
247     "Asia/Jayapura",
248     "Asia/Jerusalem",
249     "Asia/Kabul",
250     "Asia/Kamchatka",
251     "Asia/Karachi",
252     "Asia/Kashgar",
253     "Asia/Kathmandu",
254     "Asia/Katmandu",
255     "Asia/Khandyga",
256     "Asia/Kolkata",
257     "Asia/Krasnoyarsk",
258     "Asia/Kuala_Lumpur",
259     "Asia/Kuching",
260     "Asia/Kuwait",
261     "Asia/Macau",
262     "Asia/Magadan",
263     "Asia/Makassar",
264     "Asia/Manila",
265     "Asia/Muscat",
266     "Asia/Nicosia",
267     "Asia/Novokuznetsk",
268     "Asia/Novosibirsk",
269     "Asia/Omsk",
270     "Asia/Oral",
271     "Asia/Phnom_Penh",
272     "Asia/Pontianak",
273     "Asia/Pyongyang",
274     "Asia/Qatar",
275     "Asia/Qyzylorda",
276     "Asia/Rangoon",
277     "Asia/Riyadh",
278     "Asia/Sakhalin",
279     "Asia/Samarkand",
280     "Asia/Seoul",
281     "Asia/Shanghai",
282     "Asia/Singapore",
283     "Asia/Srednekolymsk",
284     "Asia/Taipei",
285     "Asia/Tashkent",
286     "Asia/Tbilisi",
287     "Asia/Tehran",
288     "Asia/Thimphu",
289     "Asia/Tokyo",
290     "Asia/Ulaanbaatar",
291     "Asia/Urumqi",
292     "Asia/Ust-Nera",
293     "Asia/Vientiane",
294     "Asia/Vladivostok",
295     "Asia/Yakutsk",
296     "Asia/Yekaterinburg",
297     "Asia/Yerevan",
298     "Atlantic/Azores",
299     "Atlantic/Bermuda",
300     "Atlantic/Canary",
301     "Atlantic/Cape_Verde",
302     "Atlantic/Faroe",
303     "Atlantic/Madeira",
304     "Atlantic/Reykjavik",
305     "Atlantic/South_Georgia",
306     "Atlantic/St_Helena",
307     "Atlantic/Stanley",
308     "Australia/Adelaide",
309     "Australia/Brisbane",
310     "Australia/Broken_Hill",
311     "Australia/Currie",
312     "Australia/Darwin",
313     "Australia/Eucla",
314     "Australia/Hobart",
315     "Australia/Lindeman",
316     "Australia/Lord_Howe",
317     "Australia/Melbourne",
318     "Australia/Perth",
319     "Australia/Sydney",
320     "Europe/Amsterdam",
321     "Europe/Andorra",
322     "Europe/Athens",
323     "Europe/Belgrade",
324     "Europe/Berlin",
325     "Europe/Bratislava",
326     "Europe/Brussels",
327     "Europe/Bucharest",
328     "Europe/Budapest",
329     "Europe/Busingen",
330     "Europe/Chisinau",
331     "Europe/Copenhagen",
332     "Europe/Dublin",
333     "Europe/Gibraltar",
334     "Europe/Guernsey",
335     "Europe/Helsinki",
336     "Europe/Isle_of_Man",
337     "Europe/Istanbul",
338     "Europe/Jersey",
339     "Europe/Kaliningrad",
340     "Europe/Kiev",
341     "Europe/Lisbon",
342     "Europe/Ljubljana",
343     "Europe/London",
344     "Europe/Luxembourg",
345     "Europe/Madrid",
346     "Europe/Malta",
347     "Europe/Mariehamn",
348     "Europe/Minsk",
349     "Europe/Monaco",
350     "Europe/Moscow",
351     "Europe/Oslo",
352     "Europe/Paris",
353     "Europe/Podgorica",
354     "Europe/Prague",
355     "Europe/Riga",
356     "Europe/Rome",
357     "Europe/Samara",
358     "Europe/San_Marino",
359     "Europe/Sarajevo",
360     "Europe/Simferopol",
361     "Europe/Skopje",
362     "Europe/Sofia",
363     "Europe/Stockholm",
364     "Europe/Tallinn",
365     "Europe/Tirane",
366     "Europe/Uzhgorod",
367     "Europe/Vaduz",
368     "Europe/Vatican",
369     "Europe/Vienna",
370     "Europe/Vilnius",
371     "Europe/Volgograd",
372     "Europe/Warsaw",
373     "Europe/Zagreb",
374     "Europe/Zaporozhye",
375     "Europe/Zurich",
376     GMT,
377     "Indian/Antananarivo",
378     "Indian/Chagos",
379     "Indian/Christmas",
380     "Indian/Cocos",
381     "Indian/Comoro",
382     "Indian/Kerguelen",
383     "Indian/Mahe",
384     "Indian/Maldives",
385     "Indian/Mauritius",
386     "Indian/Mayotte",
387     "Indian/Reunion",
388     "Pacific/Apia",
389     "Pacific/Auckland",
390     "Pacific/Bougainville",
391     "Pacific/Chatham",
392     "Pacific/Chuuk",
393     "Pacific/Easter",
394     "Pacific/Efate",
395     "Pacific/Enderbury",
396     "Pacific/Fakaofo",
397     "Pacific/Fiji",
398     "Pacific/Funafuti",
399     "Pacific/Galapagos",
400     "Pacific/Gambier",
401     "Pacific/Guadalcanal",
402     "Pacific/Guam",
403     "Pacific/Honolulu",
404     "Pacific/Johnston",
405     "Pacific/Kiritimati",
406     "Pacific/Kosrae",
407     "Pacific/Kwajalein",
408     "Pacific/Majuro",
409     "Pacific/Marquesas",
410     "Pacific/Midway",
411     "Pacific/Nauru",
412     "Pacific/Niue",
413     "Pacific/Norfolk",
414     "Pacific/Noumea",
415     "Pacific/Pago_Pago",
416     "Pacific/Palau",
417     "Pacific/Pitcairn",
418     "Pacific/Pohnpei",
419     "Pacific/Ponape",
420     "Pacific/Port_Moresby",
421     "Pacific/Rarotonga",
422     "Pacific/Saipan",
423     "Pacific/Tahiti",
424     "Pacific/Tarawa",
425     "Pacific/Tongatapu",
426     "Pacific/Truk",
427     "Pacific/Wake",
428     "Pacific/Wallis"
429 )
430 2016-04-27 18:26:04.393 NADate[11684:458251] 2005-08-30 00:00:00 +0000
431 2016-04-27 18:26:04.393 NADate[11684:458251] 2016-04-27 18:26:04
432 2016-04-27 18:26:04.394 NADate[11684:458251] 3月21日
433 Program ended with exit code: 0
View Code

 

打印结果中的数组,是时区代码

从430行开始是日期打印结果

三.注意

NSDate比较简单,大致分为两个步骤:1.创建日期  2.日期格式化(显示成什么格式)

还有一个需要注意的地方:

如果在打印的过程中,发现获取的时间与当前时间相差8个小时,不要担心,那是正常的,因为程序默认时间是美国时间.加上8个小时就好了.

希望能帮到需要的人,如果有什么不对的,请直接告诉我,我会用最短的时间改正.谢谢~

 

posted on 2016-04-27 18:23  Xib'sStory  阅读(368)  评论(0编辑  收藏  举报

导航