Pascal (Lazarus/Delphi)

Read a Single Facebook Post

See more Facebook Examples

Demonstrates how to read the contents of a single Facebook post. A post is an individual entry in a profile's feed. The profile could be a user, page, app, or group. 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.CkDateTime,
  Chilkat.DtObj,
  Chilkat.OAuth2,
  Chilkat.StringBuilder,
  Chilkat.JsonObject,
  Chilkat.Rest;

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

procedure RunDemo;
var
  success: Boolean;
  oauth2: TOAuth2;
  rest: TRest;
  postId: string;
  sbPath: TStringBuilder;
  responseJson: string;
  json: TJsonObject;
  dtime: TCkDateTime;
  bLocalTime: Boolean;
  dt: TDtObj;

begin
  success := False;

  //  This example requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  //  This example assumes a previously obtained an access token
  oauth2 := TOAuth2.Create;
  oauth2.AccessToken := 'FACEBOOK-ACCESS-TOKEN';

  rest := TRest.Create;

  //  Connect to Facebook...
  success := rest.Connect('graph.facebook.com',443,True,True);
  if (success = False) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  Provide the authentication credentials (i.e. the access key)
  rest.SetAuthOAuth2(oauth2);

  //  This example assumes a post id was already retrieved.
  //  For example, it could've been retrieved by reading the user's feed:
  //  See Parsing the Facebook User Feed for code showing how to parse the JSON feed content.

  postId := '10224048320139890_10210156138515282';

  sbPath := TStringBuilder.Create;
  sbPath.Append('/v2.7/');
  sbPath.Append(postId);

  //  Select the fields we want.
  //  This example will select almost all the possible fields.
  //  See https://developers.facebook.com/docs/graph-api/reference/post/
  rest.AddQueryParam('fields','id,message,created_time,caption,description,from,link,name,object_id,picture,place,privacy,properties,shares,source,status_type,story,targeting,to,type,updated_time,with_tags');

  responseJson := rest.FullRequestNoBody('GET',sbPath.GetAsString());
  if (rest.LastMethodSuccess = False) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  json := TJsonObject.Create;
  json.EmitCompact := False;
  json.Load(responseJson);

  //  Show the JSON in human-readable format.
  WriteLn(json.Emit());

  //  A sample JSON response is shown here.  
  //  { 
  //    "id": "12345678901234567_12345678900000004",
  //    "message": "Ignore my posts -- I'm doing some testing for Facebook related programming...",
  //    "created_time": "2016-09-29T20:46:18+0000",
  //    "from": { 
  //      "name": "John Doe",
  //      "id": "12345678901234567"
  //    },
  //    "link": "https:\/\/www.facebook.com\/photo.php?fbid=10210199026247451&set=a.1237223526054.2038240.1094202869&type=3",
  //    "object_id": "10210139026347451",
  //    "picture": "https:\/\/scontent.xx.fbcdn.net\/v\/t1.0-9\/14462791_10210199026647451_7830642117574407060_n.jpg?oh=a7f9ed10ce9cd81a82adeb541c60e2e2&oe=58ABB195",
  //    "privacy": { 
  //      "allow": "",
  //      "deny": "",
  //      "description": "Public",
  //      "friends": "",
  //      "value": "EVERYONE"
  //    },
  //    "status_type": "added_photos",
  //    "type": "photo",
  //    "updated_time": "2016-09-29T20:46:18+0000"
  //  }

  //  This is the code to parse some fields in the JSON response.
  WriteLn('type: ' + json.StringOf('type'));
  WriteLn('message: ' + json.StringOf('message'));
  WriteLn('id: ' + json.StringOf('id'));
  WriteLn('link: ' + json.StringOf('link'));
  WriteLn('privacy descripton: ' + json.StringOf('privacy.description'));

  dtime := TCkDateTime.Create;
  bLocalTime := True;
  dtime.SetFromTimestamp(json.StringOf('created_time'));
  dt := TDtObj.Create;
  dtime.ToDtObj(bLocalTime,dt);

  WriteLn(dt.Month + '/' + dt.Day + '/' + dt.Year + '  ' + dt.Hour + ':' + dt.Minute);


  oauth2.Free;
  rest.Free;
  sbPath.Free;
  json.Free;
  dtime.Free;
  dt.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.