ios-Time Class Date detailed

NSDate classes that define time

NSDate is a time class that we seldom encounter when writing programs. Today, I suddenly met, feeling very unfamiliar.

To everyone to send a blog, let everyone also review, haha!

Brother use when suddenly found that there are some bugs, we can write to verify the use of.

1, definition: nsdate *date =[nsdate date];//Current time on the addition and subtraction of time

2, action on time                                                        ,         &NB Sp                         &NBSP

nsdate *date1 = [NSDate datewithtimeintervalsincenow:3600.0*10];// From the current time, a few seconds later, the parameter represents seconds                             &N Bsp                          ,         &NB Sp                          ,         &NB Sp                   

nsdate *date3 = [NSDate datewithtimeintervalsince1970:1000];//from 1970 onwards, after a few seconds

3, calculate the time interval

Nstimeinterval interval = [date timeintervalsince1970];//the number of seconds from 1970 to a certain time

Nstimeinterval interval1 = [Date1 timeintervalsincedate:date];//calculates the interval of two time (s)

Nstimeinterval Interval2 = [date1 timeintervalsincenow];//Gets the interval between a time and the current time

NSLog (@ "%lf", Interval1);

4. Time Comparison

NSDate *date4 = [Date laterdate:date1];//gets two later (longer than 1970 years)

NSDate *date5 = [date earlierdate:date1];

Dateformatter Time Format

5. Conversion between strings and time

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

[Formater setdateformat:@ "Yyyy-mm-dd h:mm:ss"];//format the time display, the Formater format used here is exactly the same as the string format, or the conversion fails

NSString *datestr = [formater stringfromdate:date1];//convert Date to String

NSLog (@ "%@", datestr);

NSDateFormatter *formatter1 = [[NSDateFormatter alloc] init];

[Formatter1 setdateformat:@ "yyyy mm month DD Day Hh:mm:ss"];//the Formater format used here is exactly the same as the string format, or the conversion fails

[Formatter1 Settimezone:[nstimezone localtimezone]];//converts a string into a date

NSString *str = @ "November 11, 2015 11:11:11";

NSDate *date6 = [Formatter1 datefromstring:str];

NSLog (@ "%@", Date6);

6. Time Zone

Nstimezone *zone = [Nstimezone systemtimezone];//get system time zone

[Formater settimezone:zone];//Set time zone

Nsinteger TimeOff = [Zone secondsfromgmt];//get the time zone of the system green jet lag

NSLog (@ "%f", timeoff/3600.0);

NSDate *date7=[formatter1 DATEFROMSTRING:STR];

NSDate *date8 = [Date7 Datebyaddingtimeinterval:timeoff];

NSLog (@ "%@", Date8);

7. Eliminate time difference

NSString *[email protected] "November 10, 2015 11:11:11";

NSDateFormatter *formatter=[[nsdateformatter alloc] init];

[Formatter setdateformat:@ "yyyy mm month DD day HH:MM:SS"];

NSDate *date=[formatter DATEFROMSTRING:STR];

NSLog (@ "%@", date);

[Formatter Settimezone:[nstimezone timezonewithname:@ "UTC"];

NSDate *date1=[formatter DATEFROMSTRING:STR];

NSLog (@ "%@", date1);

[Formatter Settimezone:[nstimezone timezoneforsecondsfromgmt:0];

NSDate *date2=[formatter DATEFROMSTRING:STR];

NSLog (@ "%@", date2);

Nsinteger Timeoff=[[nstimezone Localtimezone] secondsfromgmt];

NSDate *date3=[date Datebyaddingtimeinterval:timeoff];

NSLog (@ "%@", date3);

8, the difference between the data

NSDate *data=[[nsdata Alloc]init];

NSString *[email protected] "1234";

NSData *data1=[str datausingencoding:nsutf8stringencoding];//Converts a string to data,nsutf8stringencoding represents the encoding format.

NSString *str1=[[nsstring alloc]initwithdata:data encoding:nsutf8stringencoding];//data Convert to String

NSLog (@ "%@", data1);//Output data type

NSLog (@ "%zi", data1.length);//Output data length

NSData *data2 = [NSData datawithcontentsofurl:[nsurl urlwithstring:@ "Http://www.iconpng.com/png/ios7-premium/tree11 . png "]];//get network data

NSLog (@ "%@", data2);

Nsmutabledata *data3 = [Nsmutabledata data];//Create an empty data

[Data3 appenddata:data];//splicing data

NSLog (@ "%@", data3);

ios-Time Class Date detailed