How to convert a date in another format ?

Posted on 2004-10-26
Last Modified: 2010-04-15
Hi everybody,

just wanted your thoughts on the best way to convert a date from a format to another.

I currently have a date represented in m/d/yyyy and I need to convert it via a function to a yyyy/mm/dd format.

Thanks for your suggestions.
Question by:The_Kingpin08
    LVL 45

    Accepted Solution

    Hi The_Kingpin08,

    There are countless ways to do this.  If you're that the input format is mm/dd/yy, then the easist is to use strtok() to split the strings.

    If the format is m/d/yyyy, strtok() will do fine with a bit of help from atoi().

    char OriginalDate[20] = "12/25/2004";
    char *TempDate;
    char NewDate[20];

    char *Month, *Day, *Year;

      TempDate = strdup (OriginalDate);  /*  Make a temporary string that we can scribble into  */
      Month = strtok (TempDate, "/");
      Day = strtok (NULL, "/");
      Year = strtok (NULL, "");

      sprintf (NewDate, "%s/%s/%s", Year, Month, Day);

    //if Month and/or Day can be a single digit, use this statement:

      sprintf (NewDate, "%s/%02d/%02d", Year, atoi(Month), atoi(Day));

    Good Luck!

    Author Comment

    Thanks a lot Kent.

    Just 1 thinng, what does the printf does ?

    LVL 45

    Expert Comment


    There are several functions in the printf() family.  I used sprintf() to generate a string in a particular format.  Related functions like printf(), fprintf(), vfprintf(), etc all do basically the same thing, except that they take slightly different inputs and write to a string (sprintf), a file (fprintf), or the terminal (printf).


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