DateTime Validation as 25-Jul-2012 15:08:23

Question

I am using below method to validate Date. How to format month in string ?

bool CDateTime :: IsValidDate(char* pcDate) //pcDate = 25-Jul-2012 15:08:23
{
    bool bVal = true;
    int iRet = 0;
    struct tm tmNewTime;   

    iRet = sscanf_s(pcDate, "%d-%d-%d %d:%d:%d", &tmNewTime.tm_mon, &tmNewTime.tm_mday, &tmNewTime.tm_year, &tmNewTime.tm_hour, &tmNewTime.tm_min, &tmNewTime.tm_sec);
    if (iRet == -1)
        bVal = false;

    if (bVal == true)
    {
        tmNewTime.tm_year -= 1900;
        tmNewTime.tm_mon -= 1;
        bVal = IsValidTm(&tmNewTime);
    }
    return bVal;

}

fyi, the `struct` in `struct tm tmNewTime;` is redundant in C++. — chris, Jul 25 '12 at 06:20
You mixed up "tm_mon" and "tm_year" in your sscanf_s statement. — Jakob S., Jul 25 '12 at 06:26
Maybe have a look at http://stackoverflow.com/questions/308390/convert-a-string-to-a-date-in-c ? — Jakob S., Jul 25 '12 at 06:29
Are you asking about how to do the actual validation, or about how to do the formatting? — Some programmer dude, Jul 25 '12 at 06:48

score 1 · Answer 1 · answered Jul 25 '12 at 06:25

1

Using strptime:

#include <time.h>
char *str = "25-Jul-2012 15:08:23";
struct tm tm;
if (strptime (str, "%d-%b-%Y %H:%M:%S", &tm) == NULL) {
   /* Bad format !! */
}

answered Jul 25 '12 at 06:25

perreal

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I Have included bit it is saying strptime identifier not found – Bokambo Jul 25 '12 at 06:37

Some programmer dude · Answer 2 · 2012-07-25T09:13:50.680

-1

The C++11 way of doing this is:

#include <iostream>
#include <iomanip>
#include <ctime>
#include <chrono>

int main()
{
    auto now = std::chrono::system_clock::now();
    auto now_c = std::chrono::system_clock::to_time_t(now);

    std::cout << "Now is " << std::put_time(std::localtime(&now_c), "%d-%b-%Y %H:%M:%S") << '\n';
}

Note: The stream I/O manipulator std::put_time is not implemented fully in all compilers yet. GCC 4.7.1 does not have it for example.

edited Jul 25 '12 at 09:13

answered Jul 25 '12 at 06:36

Some programmer dude

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The question is about validation of a date given as string, not about streaming out a date as string. – Jakob S. Jul 25 '12 at 06:43
@JakobS. To quote from the question: "How to format month in string ?" The OP _states_ he want to validate a date, but _asks_ about formatting. – Some programmer dude Jul 25 '12 at 06:47
Ok, you are right - the title does not really reflect the question. – Jakob S. Jul 25 '12 at 06:49

DateTime Validation as 25-Jul-2012 15:08:23

2 Answers2