Как конвертировать RFC дату и обратно?
Как конвертировать RFC дату и обратно?
functionDateTimeToRfcTime(
dt: TDateTime;
iDiff: integer;
blnGMT: boolean = false): string;
{*
Explanation:
iDiff is the local offset to GMT in minutes
if blnGMT then Result is UNC time else local time
e.g. local time zone: ET = GMT - 5hr = -300 minutes
dt is TDateTime of 3 Jan 2001 5:45am
blnGMT = true -> Result = 'Wed, 03 Jan 2001 05:45:00 GMT'
blnGMT = false -> Result = 'Wed, 03 Jan 2001 05:45:00 -0500'
*}
const
Weekday: array[1..7] of string =
('Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat');
Month: array[1..12] of string = (
'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec');
var
iDummy: Word;
iYear: Word;
iMonth: Word;
iDay: Word;
iHour: Word;
iMinute: Word;
iSecond: Word;
strZone: string;
begin
if blnGMT then
begin
dt := dt - iDiff / 1440;
strZone := 'GMT';
end
else
begin
iDiff := (iDiff div 60) * 100 + (iDiff mod 60);
if iDiff < 0 then
strZone := Format('-%.4d', [-iDiff])
else
strZone := Format('+%.4d', [iDiff]);
end;
DecodeDate(dt, iYear, iMonth, iDay);
DecodeTime(dt, iHour, iMinute, iSecond, iDummy);
Result := Format('%s, %.2d %s %4d %.2d:%.2d:%.2d %s', [
Weekday[DayOfWeek(dt)], iDay, Month[iMonth], iYear,
iHour, iMinute, iSecond, strZone]);
end;
function RfcTimeToDateTime(
strTime: string;
blnGMT: boolean = true): TDateTime;
{*
Explanation:
if blnGMT then Result is UNC time else local time
e.g. local time zone: ET = GMT - 5hr = -0500
strTime = 'Wed, 03 Jan 2001 05:45:00 -0500'
blnGMT = true -> FormatDateTime('...', Result) = '03.01.2001 10:45:00'
blnGMT = false -> FormatDateTime('...', Result) = '03.01.2001 05:45:00'
*}
const
wd = 'sun#mon#tue#wed#thu#fri#sat';
month = 'janfebmaraprmayjunjulaugsepoctnovdec';
var
s: string;
dd: Word;
mm: Word;
yy: Word;
hh: Word;
nn: Word;
ss: Word;
begin
s := LowerCase(Copy(strTime, 1, 3));
if Pos(s, wd) > 0 then
Delete(strTime, 1, Pos(' ', strTime));
s := Trim(Copy(strTime, 1, Pos(' ', strTime)));
Delete(strTime, 1, Length(s) + 1);
dd := StrToIntDef(s, 0);
s := LowerCase(Copy(strTime, 1, 3));
Delete(strTime, 1, 4);
mm := (Pos(s, month) div 3) + 1;
s := Copy(strTime, 1, 4);
Delete(strTime, 1, 5);
yy := StrToIntDef(s, 0);
Result := EncodeDate(yy, mm, dd);
s := strTime[1] + strTime[2];
hh := StrToIntDef(strTime[1] + strTime[2], 0);
nn := StrToIntDef(strTime[4] + strTime[5], 0);
ss := StrToIntDef(strTime[7] + strTime[8], 0);
Delete(strTime, 1, 9);
Result := Result + EncodeTime(hh, nn, ss, 0);
if (CompareText(strTime, 'gmt') <> 0) and blnGMT then
begin
hh := StrToIntDef(strTime[2] + strTime[3], 0);
nn := StrToIntDef(strTime[4] + strTime[5], 0);
if strTime[1] = '+' then
Result := Result - EncodeTime(hh, nn, 0, 0)
else
Result := Result + EncodeTime(hh, nn, 0, 0);
end;
end;
Взято с
Delphi Knowledge Basefunction RFC1123ToDateTime(Date: string): TDateTime;
var
day, month, year: Integer;
strMonth: string;
Hour, Minute, Second: Integer;
begin
try
day := StrToInt(Copy(Date, 6, 2));
strMonth := Copy(Date, 9, 3);
if strMonth = 'Jan' then month := 1
else if strMonth = 'Feb' then month := 2
else if strMonth = 'Mar' then month := 3
else if strMonth = 'Apr' then month := 4
else if strMonth = 'May' then month := 5
else if strMonth = 'Jun' then month := 6
else if strMonth = 'Jul' then month := 7
else if strMonth = 'Aug' then month := 8
else if strMonth = 'Sep' then month := 9
else if strMonth = 'Oct' then month := 10
else if strMonth = 'Nov' then month := 11
else if strMonth = 'Dec' then month := 12;
year := StrToInt(Copy(Date, 13, 4));
hour := StrToInt(Copy(Date, 18, 2));
minute := StrToInt(Copy(Date, 21, 2));
second := StrToInt(Copy(Date, 24, 2));
Result := 0;
Result := EncodeTime(hour, minute, second, 0);
Result := Result + EncodeDate(year, month, day);
except
Result := now;
end;
end;
function DateTimeToRFC1123(aDate: TDateTime): string;
const
StrWeekDay: string = 'MonTueWedThuFriSatSun';
StrMonth: string = 'JanFebMarAprMayJunJulAugSepOctNovDec';
var
Year, Month, Day: Word;
Hour, Min, Sec, MSec: Word;
DayOfWeek: Word;
begin
DecodeDate(aDate, Year, Month, Day);
DecodeTime(aDate, Hour, Min, Sec, MSec);
DayOfWeek := ((Trunc(aDate) - 2) mod 7);
Result := Copy(StrWeekDay, 1 + DayOfWeek * 3, 3) + ', ' +
Format('%2.2d %s %4.4d %2.2d:%2.2d:%2.2d',
[Day, Copy(StrMonth, 1 + 3 * (Month - 1), 3),
Year, Hour, Min, Sec]);
end;
Взято с сайта
