waldo kitty wroteOn 11/19/2014 9:17
Philippe wrote
>> I still don't know how to use at the same
time formatStr and FormatSettings in FormatDateTime.
i'm not sure i
understand your delima... perhaps you are trying to determine how
the
FormatSettings work and how you can force the same output format on
different OSes? i found the following (slightly modified by me for CLI) delphi
code that might help... the original code resides at
http://www.delphibasics.co.uk/RTL.asp?Name=FormatDateTime [1]in the code, we output the results of the various FormatDateTime usages... then
we change the values of the date and time formatting variables and
run the same
outputs again...
>> I´ll like very much to find a
tutorial or some example about the good practice to manage dates and be sure it will do the same thing on different machines ....
in some
cases, you can fall back to delphi tutorials... it can be troublesome in
some cases where things are slightly different between FPC/Lazarus
and Delphi...
the biggest problem i personally run into is that so
much example code is GUI
oriented and i still code for CLI...
anyway, here is the output of the following code...
*NOTE:* i think
we've found a bug in (fpc?) trunk or perhaps it is just an
unexpected
side effect due to the system's settings... the day and month are
reversed in the first separators line... as the comments in the code note, we're
trying to work with 5 Jun 49... but this output was done
on a US winwhatever
(vista) system... it might be getting in the way
by forcing mm/dd/yy format from
the dd/mm/yy work string... someone
else will have to speak to that as i would
expect it to do the same
in the second output set but it doesn't...
System formatting:
Working with date string = 05/06/49 01:02:03.004
Separators dd/mm/yy
hh:nn:ss = 06/05/49 01:02:03
ShortMonths mmm = May
LongMonths mmmm =
May
ShortDays ddd = Thu
LongDays dddd = Thursday
ShortDate ddddd =
5/6/2049
LongDate dddddd = Thursday, May 06, 2049
AMPM hhampm =
01AM
ShortTime t = 1:02
LongTime tt = 1:02:03
2DigitCentury
dd/mm/yyyy = 06/05/2049
Modified formatting:
Working with date
string = 05-06-49 01_02_03.004
Separators dd/mm/yy hh:nn:ss = 05-06-49
01_02_03
ShortMonths mmm = JUN
LongMonths mmmm = JUNE
ShortDays
ddd = SUN
LongDays dddd = SUNDAY
ShortDate ddddd = 05-JUN-49
LongDate dddddd = SUNDAY 05 of JUNE of 1949
AMPM hhampm = 01morning
ShortTime t = 01_02_03
LongTime tt = 01 _ 02 _ 03 . 004
2DigitCentury dd/mm/yyyy = 05-06-1949
===== snip =====
program
DTFormatting;
Show quoted text 6 lines
uses SysUtils;
var
DateStr : String;
myDate
: TDateTime;
begin
// Set up our TDateTime variable with a full
date and time :
// 5th of June 2049 at 01:02:03.004 (.004
milli-seconds)
//
// Note that 49 is treated as 2049 as follows :
// TwoDigitYearCenturyWindow => 50
// Current year => 2008 (at time of
writing)
// Subtract TwoDigitYearCenturyWindow => 1958
// 2 digit
year to be converted => 49
// Compare with the last 2 digits of 1958
=> Less
// So the year is in the next century => 2049
// (58 would
be converted to 1958)
WriteLn('System formatting:');
DateStr
:= '05/06/49 01:02:03.004';
WriteLn(' Working with date string =
'+DateStr);
myDate := StrToDateTime(DateStr);
// Demonstrate
default locale settings
// Use the DateSeparator and TimeSeparator
values
WriteLn(' Separators dd/mm/yy hh:nn:ss =
'+FormatDateTime('dd/mm/yy
hh:nn:ss', myDate));
// Use
ShortMonthNames
WriteLn(' ShortMonths mmm = '+FormatDateTime('mmm',
myDate));
// Use LongMonthNames
WriteLn(' LongMonths mmmm =
'+FormatDateTime('mmmm', myDate));
// Use ShortDayNames
WriteLn('
ShortDays ddd = '+FormatDateTime('ddd', myDate));
// Use
LongDayNames
WriteLn(' LongDays dddd = '+FormatDateTime('dddd',
myDate));
// Use the ShortDateFormat string
WriteLn(' ShortDate
ddddd = '+FormatDateTime('ddddd', myDate));
// Use the
LongDateFormat string
WriteLn(' LongDate dddddd =
'+FormatDateTime('dddddd', myDate));
// Use the TimeAmString
WriteLn(' AMPM hhampm = '+FormatDateTime('hhampm', myDate));
// Use
the ShortTimeFormat string
WriteLn(' ShortTime t =
'+FormatDateTime('t', myDate));
// Use the LongTimeFormat string
WriteLn(' LongTime tt = '+FormatDateTime('tt', myDate));
// Use the
TwoDigitCenturyWindow
WriteLn(' 2DigitCentury dd/mm/yyyy =
'+FormatDateTime('dd/mm/yyyy',
myDate));
WriteLn('');
WriteLn('Modified formatting:');
// Now change the defaults
DefaultFormatSettings.DateSeparator := '-';
DefaultFormatSettings.TimeSeparator := '_';
DefaultFormatSettings.ShortDateFormat := 'dd/mmm/yy';
DefaultFormatSettings.LongDateFormat := 'dddd dd "of" mmmm "of" yyyy';
DefaultFormatSettings.TimeAMString := 'morning';
DefaultFormatSettings.TimePMString := 'afternoon';
DefaultFormatSettings.ShortTimeFormat := 'hh:nn:ss';
DefaultFormatSettings.LongTimeFormat := 'hh : nn : ss . zzz';
DefaultFormatSettings.ShortMonthNames[6] := 'JUN';
DefaultFormatSettings.LongMonthNames[6] := 'JUNE';
DefaultFormatSettings.ShortDayNames[1] := 'SUN';
DefaultFormatSettings.LongDayNames[1] := 'SUNDAY';
DefaultFormatSettings.TwoDigitYearCenturyWindow := 75; // This means 49
is
treated as 1949
// Set up our TDateTime variable with the
same value as before
// **except that we must use the new date and
time separators**
// The TwoDigitYearCenturyWindow variable only takes
effect here
DateStr := '05-06-49 01_02_03.004';
WriteLn(' Working
with date string = '+DateStr);
Show quoted text 6 lines
myDate := StrToDateTime(DateStr);
// Use the DateSeparator and TimeSeparator values
WriteLn('
Separators dd/mm/yy hh:nn:ss = '+FormatDateTime('dd/mm/yy
hh:nn:ss',
myDate));
// Use ShortMonthNames
WriteLn(' ShortMonths mmm =
'+FormatDateTime('mmm', myDate));
// Use LongMonthNames
WriteLn('
LongMonths mmmm = '+FormatDateTime('mmmm', myDate));
// Use
ShortDayNames
WriteLn(' ShortDays ddd = '+FormatDateTime('ddd',
myDate));
// Use LongDayNames
WriteLn(' LongDays dddd =
'+FormatDateTime('dddd', myDate));
// Use the ShortDateFormat
string
WriteLn(' ShortDate ddddd = '+FormatDateTime('ddddd',
myDate));
// Use the LongDateFormat string
WriteLn(' LongDate
dddddd = '+FormatDateTime('dddddd', myDate));
// Use the
TimeAmString
WriteLn(' AMPM hhampm = '+FormatDateTime('hhampm',
myDate));
// Use the ShortTimeFormat string
WriteLn(' ShortTime t
= '+FormatDateTime('t', myDate));
// Use the LongTimeFormat
string
WriteLn(' LongTime tt = '+FormatDateTime('tt', myDate));
// Use the TwoDigitCenturyWindow
WriteLn(' 2DigitCentury dd/mm/yyyy =
'+FormatDateTime('dd/mm/yyyy',
myDate));
end.
===== snip
=====
Thanks to you, to Graeme and Michael!
That almost what I was
looking for. And did not find. Quite simple indeed!
More as a
curiosity: how should one use formatDateTime( formatStr, dt, formatSettings);
Philippe
Links:
------
[1]
http://www.delphibasics.co.uk/RTL.asp?Name=FormatDateTime
