IOS gets the current time and calculates the Age (difference)

Get current time

        NSDate *now = [NSDate date];        NSLog (@ "Now date was:%@", now);            Nscalendar *calendar = [Nscalendar Currentcalendar];        Nsuinteger unitflags = Nsyearcalendarunit | Nsmonthcalendarunit | Nsdaycalendarunit | Nshourcalendarunit | Nsminutecalendarunit | Nssecondcalendarunit;        nsdatecomponents *datecomponent = [Calendar components:unitflags fromdate:now];            int year = [datecomponent year];        int month = [datecomponent month];        int day = [Datecomponent day];        int hour = [Datecomponent hour];        int minute = [datecomponent minute];        int second = [datecomponent second];            NSLog (@ "Year was:%d", year);        NSLog (@ "Month is:%d", month);        NSLog (@ "Day was:%d", day);        NSLog (@ "Hour is:%d", hour);        NSLog (@ "Minute is:%d", minute);        NSLog (@ "Second is:%d", second);

Calculate age

The first is only the age of the year difference

    Calculate Age    NSString *birth = @ "1993-10-30";    NSDateFormatter *dateformatter = [[NSDateFormatter alloc]init];    [Dateformatter setdateformat:@ "Yyyy-mm-dd"];    Birthday    NSDate *birthday = [Dateformatter Datefromstring:birth];    Current time    nsstring *currentdatestr = [dateformatter stringfromdate:[nsdate Date]];    NSDate *currentdate = [Dateformatter datefromstring:currentdatestr];    NSLog (@ "currentdate%@ birthDay%@", Currentdatestr,birth);    Nstimeinterval time=[currentdate Timeintervalsincedate:birthday];    int age = ((int) time)/(3600*24*365);    NSLog (@ ' year%d ', age);

The other one draws details to the age of the day

Nscalendar *calendar = [Nscalendar currentcalendar];//defines a Nscalendar object nsdate *nowdate = [NSDate Date];    NSString *birth = @ "1900-10-30";    NSDateFormatter *dateformatter = [[NSDateFormatter alloc]init];    [Dateformatter setdateformat:@ "Yyyy-mm-dd"];        Birthday NSDate *birthday = [Dateformatter Datefromstring:birth]; Used to get the detailed time difference unsigned int unitflags = Nsyearcalendarunit | Nsmonthcalendarunit | Nsdaycalendarunit | Nshourcalendarunit | Nsminutecalendarunit |    Nssecondcalendarunit;        nsdatecomponents *date = [Calendar components:unitflags fromdate:birthday todate:nowdate options:0]; if ([date year] >0) {NSLog (@ "%@", [NSString stringWithFormat: (@ "%ld years%ld months%ld days"), (long) [date year], (long) [Date m    Onth], (long) [date Day]]); The Else if ([date month] >0) {NSLog (@ "%@", [NSString stringWithFormat: (@ "%ld month%ld Days"), (long) [date month], (long    ) [Date Day]]; } else if ([date day]>0) {NSLog (@ "%@", [NSString stringWithFormat: (@ "%ld days"),(long)    [Date Day]]);    } else {NSLog (@ "0 days"); }

string, date, int conversion

This entry: http://blog.csdn.net/tt5267621/article/details/7720434

1. String conversion to date

nsdateformatter* DateFormat = [[NSDateFormatter alloc] init];//instantiates a NSDateFormatter object
[DateFormat setdateformat:@ "Yyyy-mm-dd HH:mm:ss"];//set the time format, where you can set the format you need
NSDate *date =[dateformat datefromstring:@ "1980-01-01 00:00:01"];

2. Convert Date to String

nsdateformatter* DateFormat = [[NSDateFormatter alloc] init];//instantiates a NSDateFormatter object
[DateFormat setdateformat:@ "Yyyy-mm-dd HH:mm:ss"];//set the time format, where you can set the format you need
NSString *currentdatestr = [DateFormat stringfromdate:[nsdate Date]];

3. String to int

Convert NSString to int
NSString *anumberstring = @ "123";
int i = [anumberstring intvalue];

4, int to string

Convert int to NSString
int anumber = 123;
NSString *astring = [NSString stringwithformat:@ "%d", anumber];

IOS gets the current time and calculates the Age (difference)