(Delphi DLL) JSON Date Parsing

Demonstrates how to parse date/time strings from JSON.

Note: This example uses the DtOf and DateOf methods introduced in Chilkat v9.5.0.73

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, DtObj, JsonObject, CkDateTime;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
json: HCkJsonObject;
dateTime: HCkDateTime;
dt: HCkDtObj;
getAsLocal: Boolean;

begin
json := CkJsonObject_Create();
CkJsonObject_putEmitCompact(json,False);

// First, let's create JSON containing some date/time strings.
CkJsonObject_UpdateString(json,'test.timestamp','2018-01-30T20:35:00Z');
CkJsonObject_UpdateString(json,'test.rfc822','Tue, 24 Apr 2018 08:47:03 -0500');
CkJsonObject_UpdateString(json,'test.dateStrings[0]','2018-01-30T20:35:00Z');
CkJsonObject_UpdateString(json,'test.dateStrings[1]','Tue, 24 Apr 2018 08:47:03 -0500');
CkJsonObject_UpdateNumber(json,'test.StartLoggingTime','1446834998.695');
CkJsonObject_UpdateNumber(json,'test.Expiration','1442877512.0');
CkJsonObject_UpdateInt(json,'test.StartTime',1518867432);

Memo1.Lines.Add(CkJsonObject__emit(json));

// We've built the following JSON:

// {
//   "test": {
//     "timestamp": "2018-01-30T20:35:00Z",
//     "rfc822": "Tue, 24 Apr 2018 08:47:03 -0500",
//     "dateStrings": [
//       "2018-01-30T20:35:00Z",
//       "Tue, 24 Apr 2018 08:47:03 -0500"
//     ],
//     "StartLoggingTime": 1446834998.695,
//     "Expiration": 1442877512.0,
//     "StartTime": 1518867432
//   }
// }

// Use the DateOf and DtOf methods to load Chilkat date/time objects with the date/time values.
// The CkDateTime object is primarily for loading a date/time from numerous formats, and then getting
// the date/time in various formats.  Thus, it's primarly for date/time format conversion.
// The DtObj object holds a date/time where the individual components (day, month, year, hour, minutes, etc.) are 
// immediately accessible as integers.
dateTime := CkDateTime_Create();
dt := CkDtObj_Create();
getAsLocal := False;

// Load the date/time at test.timestamp into the dateTime object.
success := CkJsonObject_DateOf(json,'test.timestamp',dateTime);
Memo1.Lines.Add(CkDateTime__getAsTimestamp(dateTime,getAsLocal));
Memo1.Lines.Add(IntToStr(CkDateTime_GetAsUnixTime(dateTime,False)));
Memo1.Lines.Add(CkDateTime__getAsRfc822(dateTime,getAsLocal));

success := CkJsonObject_DateOf(json,'test.rfc822',dateTime);
Memo1.Lines.Add(CkDateTime__getAsTimestamp(dateTime,getAsLocal));

CkJsonObject_putI(json,0);
success := CkJsonObject_DateOf(json,'test.dateStrings[i]',dateTime);
Memo1.Lines.Add(CkDateTime__getAsTimestamp(dateTime,getAsLocal));

CkJsonObject_putI(json,1);
success := CkJsonObject_DateOf(json,'test.dateStrings[i]',dateTime);
Memo1.Lines.Add(CkDateTime__getAsTimestamp(dateTime,getAsLocal));

success := CkJsonObject_DateOf(json,'test.StartLoggingTime',dateTime);
Memo1.Lines.Add(CkDateTime__getAsTimestamp(dateTime,getAsLocal));

success := CkJsonObject_DateOf(json,'test.Expiration',dateTime);
Memo1.Lines.Add(CkDateTime__getAsTimestamp(dateTime,getAsLocal));

success := CkJsonObject_DateOf(json,'test.StartTime',dateTime);
Memo1.Lines.Add(CkDateTime__getAsTimestamp(dateTime,getAsLocal));

// Output so far:

// 	2018-01-30T20:35:00Z
// 	1517344500
// 	Tue, 30 Jan 2018 20:35:00 GMT
// 	2018-04-24T13:47:03Z
// 	2018-01-30T20:35:00Z
// 	2018-04-24T13:47:03Z
// 	2015-11-07T00:36:38Z
// 	2015-09-22T04:18:32Z
// 	2018-02-17T17:37:12Z

// Now load the date/time strings into the dt object:
success := CkJsonObject_DtOf(json,'test.timestamp',getAsLocal,dt);
Memo1.Lines.Add('month=' + IntToStr(CkDtObj_getMonth(dt)) + ', day=' + IntToStr(CkDtObj_getDay(dt)) + ', year=' + IntToStr(CkDtObj_getYear(dt))
     + ', hour=' + IntToStr(CkDtObj_getHour(dt)) + ', minute=' + IntToStr(CkDtObj_getMinute(dt)));

success := CkJsonObject_DtOf(json,'test.rfc822',getAsLocal,dt);
Memo1.Lines.Add('month=' + IntToStr(CkDtObj_getMonth(dt)) + ', day=' + IntToStr(CkDtObj_getDay(dt)) + ', year=' + IntToStr(CkDtObj_getYear(dt))
     + ', hour=' + IntToStr(CkDtObj_getHour(dt)) + ', minute=' + IntToStr(CkDtObj_getMinute(dt)));

CkJsonObject_putI(json,0);
success := CkJsonObject_DtOf(json,'test.dateStrings[i]',getAsLocal,dt);
Memo1.Lines.Add('month=' + IntToStr(CkDtObj_getMonth(dt)) + ', day=' + IntToStr(CkDtObj_getDay(dt)) + ', year=' + IntToStr(CkDtObj_getYear(dt))
     + ', hour=' + IntToStr(CkDtObj_getHour(dt)) + ', minute=' + IntToStr(CkDtObj_getMinute(dt)));

CkJsonObject_putI(json,1);
success := CkJsonObject_DtOf(json,'test.dateStrings[i]',getAsLocal,dt);
Memo1.Lines.Add('month=' + IntToStr(CkDtObj_getMonth(dt)) + ', day=' + IntToStr(CkDtObj_getDay(dt)) + ', year=' + IntToStr(CkDtObj_getYear(dt))
     + ', hour=' + IntToStr(CkDtObj_getHour(dt)) + ', minute=' + IntToStr(CkDtObj_getMinute(dt)));

success := CkJsonObject_DtOf(json,'test.StartLoggingTime',getAsLocal,dt);
Memo1.Lines.Add('month=' + IntToStr(CkDtObj_getMonth(dt)) + ', day=' + IntToStr(CkDtObj_getDay(dt)) + ', year=' + IntToStr(CkDtObj_getYear(dt))
     + ', hour=' + IntToStr(CkDtObj_getHour(dt)) + ', minute=' + IntToStr(CkDtObj_getMinute(dt)));

success := CkJsonObject_DtOf(json,'test.Expiration',getAsLocal,dt);
Memo1.Lines.Add('month=' + IntToStr(CkDtObj_getMonth(dt)) + ', day=' + IntToStr(CkDtObj_getDay(dt)) + ', year=' + IntToStr(CkDtObj_getYear(dt))
     + ', hour=' + IntToStr(CkDtObj_getHour(dt)) + ', minute=' + IntToStr(CkDtObj_getMinute(dt)));

success := CkJsonObject_DtOf(json,'test.StartTime',getAsLocal,dt);
Memo1.Lines.Add('month=' + IntToStr(CkDtObj_getMonth(dt)) + ', day=' + IntToStr(CkDtObj_getDay(dt)) + ', year=' + IntToStr(CkDtObj_getYear(dt))
     + ', hour=' + IntToStr(CkDtObj_getHour(dt)) + ', minute=' + IntToStr(CkDtObj_getMinute(dt)));

// Output:

// month=1, day=30, year=2018, hour=20, minute=35
// month=4, day=24, year=2018, hour=13, minute=47
// month=1, day=30, year=2018, hour=20, minute=35
// month=4, day=24, year=2018, hour=13, minute=47
// month=11, day=6, year=2015, hour=18, minute=36
// month=9, day=21, year=2015, hour=23, minute=18
// month=2, day=17, year=2018, hour=11, minute=37

CkJsonObject_Dispose(json);
CkDateTime_Dispose(dateTime);
CkDtObj_Dispose(dt);

end;