NSDateFormatter 格式拾掇
[formattersetLocale:[[[NSLocale alloc]initWithLocaleIdentifier
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yyyy 4位年
MM 月
d~dd 日
hh 时
HH 24小时
mm 分
ss 秒
a~aaa AM/PM
EEE 英文星期
MMM 英文月
Z~ZZZ 时区
ZZZZ
K
G~GGG AD
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))
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)
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)
Y/YYYY: (Full Year, starting from the Sunday of the 1st week ofyear) 这个年份未知干嘛用的
YY/YYY: (2 Digits Year, starting from the Sunday of the 1st weekof 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
| Field | Sym. | No. | Example | Description | ||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| era | G | 1..3 | AD | Era -Replaced with the Era string for the current date. One to threeletters for the abbreviated form, four letters for the long form,five for the narrow form. | ||||||||||||||||||||||||||||||||||||
| 4 | Anno Domini | |||||||||||||||||||||||||||||||||||||||
| 5 | A | |||||||||||||||||||||||||||||||||||||||
| year | y | 1..n | 1996 |
Year. Normally the length specifies the padding, but for twoletters it also specifies the maximum length. Example:
|
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| Y | 1..n | 1997 | Year (of "Week of Year"), used in ISO year-week calendar. Maydiffer from calendar year. | |||||||||||||||||||||||||||||||||||||
| u | 1..n | 4601 | Extended year. This is a single number designating the year ofthis calendar system, encompassing all supra-year fields. Forexample, for the Julian calendar system, year numbers are positive,with an era of BCE or CE. An extended year value for the Juliancalendar system assigns positive values to CE years and negativevalues to BCE years, with 1 BCE being year 0. | |||||||||||||||||||||||||||||||||||||
| quarter | Q | 1..2 | 02 | Quarter - Use one or two for the numerical quarter, three for theabbreviation, or four for the full name. | ||||||||||||||||||||||||||||||||||||
| 3 | Q2 | |||||||||||||||||||||||||||||||||||||||
| 4 | 2nd quarter | |||||||||||||||||||||||||||||||||||||||
| q | 1..2 | 02 | Stand-Alone Quarter - Use one or two for the numericalquarter, three for the abbreviation, or four for the fullname. | |||||||||||||||||||||||||||||||||||||
| 3 | Q2 | |||||||||||||||||||||||||||||||||||||||
| 4 | 2nd quarter | |||||||||||||||||||||||||||||||||||||||
| month | M | 1..2 | 09 | Month- Use one or two for the numerical month, three for theabbreviation, or four for the full name, or five for the narrowname. | ||||||||||||||||||||||||||||||||||||
| 3 | Sept | |||||||||||||||||||||||||||||||||||||||
| 4 | September | |||||||||||||||||||||||||||||||||||||||
| 5 | S | |||||||||||||||||||||||||||||||||||||||
| L | 1..2 | 09 | Stand-Alone Month - Use one or two for the numerical month,three for the abbreviation, or four for the full name, or 5 for thenarrow name. | |||||||||||||||||||||||||||||||||||||
| 3 | Sept | |||||||||||||||||||||||||||||||||||||||
| 4 | September | |||||||||||||||||||||||||||||||||||||||
| 5 | S | |||||||||||||||||||||||||||||||||||||||
| week | w | 1..2 | 27 | Week of Year. | ||||||||||||||||||||||||||||||||||||
| W | 1 | 3 | Week of Month | |||||||||||||||||||||||||||||||||||||
| day | d | 1..2 | 1 | Date - Day of the month | ||||||||||||||||||||||||||||||||||||
| D | 1..3 | 345 | Day of year | |||||||||||||||||||||||||||||||||||||
| F | 1 |
2 |
Day of Week in Month. The example is for the 2nd Wed inJuly | |||||||||||||||||||||||||||||||||||||
| g | 1..n | 2451334 | Modified Julian day. This is different from the conventionalJulian day number in two regards. First, it demarcates days atlocal zone midnight, rather than noon GMT. Second, it is a localnumber; that is, it depends on the local time zone. It can bethought of as a single number that encompasses all the date-relatedfields. | |||||||||||||||||||||||||||||||||||||
| week day |
E | 1..3 | Tues | Dayof week - Use one through three letters for the short day, or fourfor the full name, or five for the narrow name. | ||||||||||||||||||||||||||||||||||||
| 4 | Tuesday | |||||||||||||||||||||||||||||||||||||||
| 5 | T | |||||||||||||||||||||||||||||||||||||||
| e | 1..2 | 2 | Localday of week. Same as E except adds a numeric value that will dependon the local starting day of the week, using one or two letters.For this example, Monday is the first day of the week. | |||||||||||||||||||||||||||||||||||||
| 3 | Tues | |||||||||||||||||||||||||||||||||||||||
| 4 | Tuesday | |||||||||||||||||||||||||||||||||||||||
| 5 | T | |||||||||||||||||||||||||||||||||||||||
| c | 1 | 2 | Stand-Alone local day of week - Use one letter for the localnumeric value (same as 'e'), three for the short day, or four forthe full name, or five for the narrow name. | |||||||||||||||||||||||||||||||||||||
| 3 | Tues | |||||||||||||||||||||||||||||||||||||||
| 4 | Tuesday | |||||||||||||||||||||||||||||||||||||||
| 5 | T | |||||||||||||||||||||||||||||||||||||||
| period | a | 1 | AM | AM or PM | ||||||||||||||||||||||||||||||||||||
| hour | h | 1..2 | 11 | Hour [1-12]. | ||||||||||||||||||||||||||||||||||||
| H | 1..2 | 13 | Hour [0-23]. | |||||||||||||||||||||||||||||||||||||
| K | 1..2 | 0 | Hour [0-11]. | |||||||||||||||||||||||||||||||||||||
| k | 1..2 | 24 | Hour [1-24]. | |||||||||||||||||||||||||||||||||||||
| minute | m | 1..2 | 59 | Minute. Use one or two for zero padding. | ||||||||||||||||||||||||||||||||||||
| second | s | 1..2 | 12 | Second. Use one or two for zero padding. | ||||||||||||||||||||||||||||||||||||
| S | 1..n | 3457 | Fractional Second - rounds to the count of letters. (example isfor 12.34567) | |||||||||||||||||||||||||||||||||||||
| A | 1..n | 69540000 | Milliseconds in day. This field behaves exactly like acomposite of all time-related fields, not including the zonefields. As such, it also reflects discontinuities of those fieldson DST transition days. On a day of DST onset, it will jumpforward. On a day of DST cessation, it will jump backward. Thisreflects the fact that is must be combined with the offset field toobtain a unique local time value. | |||||||||||||||||||||||||||||||||||||
| zone | z | 1..3 | PDT | Timezone - Use one to three letters for the short timezone or fourfor the full name. For more information, see AppendixJ: Time Zone Display Names | ||||||||||||||||||||||||||||||||||||
| 4 | Pacific DaylightTime | |||||||||||||||||||||||||||||||||||||||
| Z | 1..3 | -0800 | Useone to three letters for RFC 822, four letters for GMT format. | |||||||||||||||||||||||||||||||||||||
| 4 | GMT-08:00 | |||||||||||||||||||||||||||||||||||||||
| v | 1 | PT | Useone letter for short wall (generic) time, four for long wall time.For more information, see AppendixJ: Time Zone Display Names | |||||||||||||||||||||||||||||||||||||
| 4 | Pacific Time |
All non-letter character represent themselves in a pattern,except for the single quote. It is used to 'escape' letters. Twosingle quotes in a row, whether inside or outside a quotedsequence, represent a 'real' single quote.