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copied!<p>You can find Iso-8601 conversion routines in our <a href="http://synopse.info/fossil/finfo?name=SynCommons.pas" rel="noreferrer">SynCommons unit</a>. </p> <p>It has been deeply optimized for speed, so it's much faster than the DateTimeToString() functions and such, but of course, code is more difficult to follow. ;)</p> <pre><code>procedure Iso8601ToDateTimePUTF8CharVar(P: PUTF8Char; L: integer; var result: TDateTime); var i: integer; B: cardinal; Y,M,D, H,MI,SS: cardinal; // we expect 'YYYYMMDDThhmmss' format but we handle also 'YYYY-MM-DD hh:mm:ss' begin result := 0; if P=nil then exit; if L=0 then L := StrLen(P); if L<4 then exit; // we need 'YYYY' at least if P[0]='T' then dec(P,8) else begin B := ConvertHexToBin[ord(P[0])]; // first digit if B>9 then exit else Y := B; // fast check '0'..'9' for i := 1 to 3 do begin B := ConvertHexToBin[ord(P[i])]; // 3 other digits if B>9 then exit else Y := Y*10+B; end; if P[4] in ['-','/'] then begin inc(P); dec(L); end; // allow YYYY-MM-DD D := 1; if L>=6 then begin // YYYYMM M := ord(P[4])*10+ord(P[5])-(48+480); if (M=0) or (M>12) then exit; if P[6] in ['-','/'] then begin inc(P); dec(L); end; // allow YYYY-MM-DD if L>=8 then begin // YYYYMMDD D := ord(P[6])*10+ord(P[7])-(48+480); if (D=0) or (D>MonthDays[true][M]) then exit; // worse is leap year=true end; end else M := 1; if M>2 then // inlined EncodeDate(Y,M,D) dec(M,3) else if M>0 then begin inc(M,9); dec(Y); end; with Div100(Y) do result := (146097*YDiv100) shr 2 + (1461*YMod100) shr 2 + (153*M+2) div 5+D-693900; if (L<15) or not(P[8] in [' ','T']) then exit; end; H := ord(P[9])*10+ord(P[10])-(48+480); if P[11]=':' then inc(P); // allow hh:mm:ss MI := ord(P[11])*10+ord(P[12])-(48+480); if P[13]=':' then inc(P); // allow hh:mm:ss SS := ord(P[13])*10+ord(P[14])-(48+480); if (H<24) and (MI<60) and (SS<60) then // inlined EncodeTime() result := result + (H * (MinsPerHour * SecsPerMin * MSecsPerSec) + MI * (SecsPerMin * MSecsPerSec) + SS * MSecsPerSec) / MSecsPerDay; end; </code></pre> <p>This is able to handle a very fast conversion from an UTF-8 encoded buffer into a <code>TDateTime</code>. For all constants dependencies, check the unit source code.</p>

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