Pascal (Lazarus/Delphi)

Create more Complex JSON Document

See more JSON Examples

Sample code to create the following JSON document:

    {  
        "Title": "The Cuckoo's Calling",  
        "Author": "Robert Galbraith",  
        "Genre": "classic crime novel",  
        "Detail": {  
            "Publisher": "Little Brown",  
            "Publication_Year": 2013,  
            "ISBN-13": 9781408704004,  
            "Language": "English",  
            "Pages": 494  
        },  
        "Price": [  
            {  
                "type": "Hardcover",  
                "price": 16.65  
            },  
            {  
                "type": "Kindle Edition",  
                "price": 7.00  
            }  
        ]  
    }  

Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.JsonArray,
  Chilkat.JsonObject;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  json: TJsonObject;
  index: Integer;
  detail: TJsonObject;
  aPrice: TJsonArray;
  priceObj: TJsonObject;

begin
  success := False;

  json := TJsonObject.Create;

  //  The only reason for failure in the following lines of code would be an out-of-memory condition..

  //  An index value of -1 is used to append at the end.
  index := -1;

  success := json.AddStringAt(-1,'Title','The Cuckoo''s Calling');
  success := json.AddStringAt(-1,'Author','Robert Galbraith');
  success := json.AddStringAt(-1,'Genre','classic crime novel');

  //  Let's create the Detail JSON object:
  detail := TJsonObject.Create;
  json.AppendObject2('Detail',detail);

  success := detail.AddStringAt(-1,'Publisher','Little Brown');
  success := detail.AddIntAt(-1,'Publication_Year',2013);
  success := detail.AddNumberAt(-1,'ISBN-13','9781408704004');
  success := detail.AddStringAt(-1,'Language','English');
  success := detail.AddIntAt(-1,'Pages',494);

  //  Add the array for Price
  aPrice := TJsonArray.Create;
  json.AppendArray2('Price',aPrice);

  //  Entry in aPrice will be a JSON object.

  //  Append a new/empty ojbect to the end of the aPrice array.
  priceObj := TJsonObject.Create;

  aPrice.AddObjectAt2(-1,priceObj);
  success := priceObj.AddStringAt(-1,'type','Hardcover');
  success := priceObj.AddNumberAt(-1,'price','16.65');

  aPrice.AddObjectAt2(-1,priceObj);
  success := priceObj.AddStringAt(-1,'type','Kindle Edition');
  success := priceObj.AddNumberAt(-1,'price','7.00');

  json.EmitCompact := False;
  WriteLn(json.Emit());


  json.Free;
  detail.Free;
  aPrice.Free;
  priceObj.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.