- (void) setDateFormat: (NSString*) format;
		
    The functions setDateFormat() and setDateDelimiter() defines a date format which will be used when you get or date as a string.
    The delimiter can be any. Usually ./-
    Formats are:
    
    - dmy : day-month-year
    
- mdy : month-day-year
    
- ymd : year-month-day
    
- asis : year-month-day without delimiter, i.e. YYYYMMDD
    
    
- (void) setDateDelimiter: (char) c;
{
    // your code
    [dbf setDateFormat:@"dmy"];
    [dbf setDateDelimiter:'/'];
    // your code
}