Finne ut år

[Zaggi]

Hei, jeg er ganske fersk i C++, har drivd og lest noen guider på nett og har nettop bestilt en bok, og jeg lurer på om det er noen funksjoner som viser hvilket år man er i nå, noe slikt som year() så kommer det 2006, jeg lurer også på om det er mulig og skifte titel i programmet når man kjører det og skifter icon på programmet.

 

 

 

-Zaggi

[MadsFN]

velkommen til forumet. (mer vet jeg ikke)

[Zaggi]

velkommen til forumet.

6420142[/snapback]

 

Takk

[Dead_Rabbit]

http://www.cppreference.com/stddate/asctime.html

Håper det hjelper.

Endret 2. juli 2006 av zirener

[Zaggi]

http://www.cppreference.com/stddate/asctime.html

Håper det hjelper.

6420624[/snapback]

 

 

Takk for svar!

 

Tror du at du kunne gi koden for og få fram året også?

Kommer ingen vei, som jeg ser på det tror jeg at det skal være asctime(ptr->tm_year);

men det funker ikke, og jeg aner ikke hva ellers det kan være

[cougar]

Standardbiblioteket for tid er ikke spesielt bra, det du enklest får fra <ctime>-metodene er antall sekunder siden 1970 en gang og det er både dårlig med dokumentasjon og vrient å få ut årstallet. Ville heller funnet på noe annet å leke meg med tror jeg

 

Selv bruker jeg Boost-biblioteket til slike ting, de har bl.a. et bra bibliotek for tid/kalender osv med ok dokumentasjon:

Boost's hjemmeside

Boost's date_time-bibliotek

 

Der står det eksempler på bruk av biblioteket også. Hvis du er helt nybegynner er det kanskje litt vanskelig å få brukt Boost, men slik ville jeg gjort det i hvert fall...

[lnostdal]

#include <iostream>
#include <time.h>

using namespace std;

int main(){
 {time_t tmp = time(NULL); tm* the_time = localtime(&tmp);
   cout << 1900 + the_time->tm_year << endl;}
 return 0;}

 

lars@ibmr52:~/programming/c$ g++ -g -Wall test.cpp -o test && ./test

2006

 

fra man-siden (du kjører linux, sannt?):

CTIME(3)                                                            Linux Programmer’s Manual                                                            CTIME(3)

 

NAME

      asctime, ctime, gmtime, localtime, mktime, asctime_r, ctime_r, gmtime_r, localtime_r - transform date and time to broken-down time or ASCII

 

SYNOPSIS

      #include <time.h>

 

      char *asctime(const struct tm *tm);

      char *asctime_r(const struct tm *tm, char *buf);

 

      char *ctime(const time_t *timep);

      char *ctime_r(const time_t *timep, char *buf);

 

      struct tm *gmtime(const time_t *timep);

      struct tm *gmtime_r(const time_t *timep, struct tm *result);

 

      struct tm *localtime(const time_t *timep);

      struct tm *localtime_r(const time_t *timep, struct tm *result);

 

      time_t mktime(struct tm *tm);

 

DESCRIPTION

      The  ctime(),  gmtime() and localtime() functions all take an argument of data type time_t which represents calendar time.  When interpreted as an absolute

      time value, it represents the number of seconds elapsed since 00:00:00 on January 1, 1970, Coordinated Universal Time (UTC).

 

      The asctime() and mktime() functions both take an argument representing broken-down time which is a representation separated into year, month, day, etc.

 

      Broken-down time is stored in the structure tm which is defined in <time.h> as follows:

 

              struct tm {

                      int    tm_sec;        /* seconds */

                      int    tm_min;        /* minutes */

                      int    tm_hour;        /* hours */

                      int    tm_mday;        /* day of the month */

                      int    tm_mon;        /* month */

                      int    tm_year;        /* year */

                      int    tm_wday;        /* day of the week */

                      int    tm_yday;        /* day in the year */

                      int    tm_isdst;      /* daylight saving time */

              };

 

      The members of the tm structure are:

 

      tm_sec The number of seconds after the minute, normally in the range 0 to 59, but can be up to 61 to allow for leap seconds.

 

      tm_min The number of minutes after the hour, in the range 0 to 59.

 

      tm_hour

              The number of hours past midnight, in the range 0 to 23.

 

      tm_mday

              The day of the month, in the range 1 to 31.

 

      tm_mon The number of months since January, in the range 0 to 11.

 

      tm_year

              The number of years since 1900.

 

      tm_wday

              The number of days since Sunday, in the range 0 to 6.

 

      tm_yday

              The number of days since January 1, in the range 0 to 365.

 

      tm_isdst

              A flag that indicates whether daylight saving time is in effect at the time described.  The value is positive if daylight saving time is in  effect,

              zero if it is not, and negative if the information is not available.

 

      The call ctime(t) is equivalent to asctime(localtime(t)).  It converts the calendar time t into a string of the form

 

              "Wed Jun 30 21:49:08 1993\n"

 

      The  abbreviations  for  the  days of the week are ‘Sun’, ‘Mon’, ‘Tue’, ‘Wed’, ‘Thu’, ‘Fri’, and ‘Sat’.  The abbreviations for the months are ‘Jan’, ‘Feb’,

      ‘Mar’, ‘Apr’, ‘May’, ‘Jun’, ‘Jul’, ‘Aug’, ‘Sep’, ‘Oct’, ‘Nov’, and ‘Dec’.  The return value points to a statically allocated string which  might  be  over‐

      written  by  subsequent  calls  to any of the date and time functions.  The function also sets the external variable tzname (see tzset(3)) with information

      about the current time zone.  The re-entrant version ctime_r() does the same, but stores the string in a user-supplied buffer of length  at  least  26.  It

      need not set tzname.

 

      The  gmtime()  function  converts  the calendar time timep to broken-down time representation, expressed in Coordinated Universal Time (UTC). It may return

      NULL when the year does not fit into an integer.  The return value points to a statically allocated struct which might be overwritten by  subsequent  calls

      to any of the date and time functions.  The gmtime_r() function does the same, but stores the data in a user-supplied struct.

 

      The localtime() function converts the calendar time timep to broken-time representation, expressed relative to the user’s specified time zone.    The func‐

      tion acts as if it called tzset(3) and sets the external variables tzname with information about the  current  time  zone,  timezone  with  the  difference

      between  Coordinated  Universal Time (UTC) and local standard time in seconds, and daylight to a non-zero value if daylight savings time rules apply during

      some part of the year.  The return value points to a statically allocated struct which might be overwritten by subsequent calls to any of the date and time

      functions.  The localtime_r() function does the same, but stores the data in a user-supplied struct. It need not set tzname.

 

      The asctime() function converts the broken-down time value tm into a string with the same format as ctime().  The return value points to a statically allo‐

      cated string which might be overwritten by subsequent calls to any of the date and time functions.  The asctime_r() function does the same, but stores  the

      string in a user-supplied buffer of length at least 26.

 

      The  mktime() function converts a broken-down time structure, expressed as local time, to calendar time representation.  The function ignores the specified

      contents of the structure members tm_wday and tm_yday and recomputes them from the other information in the broken-down time structure.  If structure  mem‐

      bers  are  outside  their  legal  interval, they will be normalized (so that, e.g., 40 October is changed into 9 November).  Calling mktime() also sets the

      external variable tzname with information about the current time zone.  If the specified broken-down time cannot be represented as calendar  time  (seconds

      since the epoch), mktime() returns a value of (time_t)(-1) and does not alter the tm_wday and tm_yday members of the broken-down time structure.

 

RETURN VALUE

      Each of these functions returns the value described, or NULL (-1 in case of mktime()) in case an error was detected.

 

NOTES

      The  four  functions asctime(), ctime(), gmtime() and localtime() return a pointer to static data and hence are not thread-safe.  Thread-safe versions asc‐

      time_r(), ctime_r(), gmtime_r() and localtime_r() are specified by SUSv2, and available since libc 5.2.5.

 

NOTES

      The  four  functions asctime(), ctime(), gmtime() and localtime() return a pointer to static data and hence are not thread-safe.  Thread-safe versions asc‐

      time_r(), ctime_r(), gmtime_r() and localtime_r() are specified by SUSv2, and available since libc 5.2.5.

 

      In many implementations, including glibc, a 0 in tm_mday is interpreted as meaning the last day of the preceding month.

 

      The glibc version of struct tm has additional fields

 

              long tm_gmtoff;          /* Seconds east of UTC */

              const char *tm_zone;      /* Timezone abbreviation */

 

      defined when _BSD_SOURCE was set before including <time.h>.  This is a BSD extension, present in 4.3BSD-Reno.

 

CONFORMING TO

      SVID 3, POSIX, 4.3BSD, ISO 9899

 

SEE ALSO

      date(1), gettimeofday(2), time(2), utime(2), clock(3), difftime(3), strftime(3), strptime(3), tzset(3)

 

Endret 2. juli 2006 av lnostdal

[Zaggi]

Takk skal dere ha, det finker perfekt!

 

er det også mulig til og skifte titelen i programmet istedet for C:\---- ? går det også ann og skifte iconen?

 

Takker igjen:)

 

 

 

 

 

 

 

 

-Zaggi