(Delphi ActiveX) Read a Single Facebook Post

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.

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

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
oauth2: TChilkatOAuth2;
rest: TChilkatRest;
success: Integer;
postId: WideString;
sbPath: TChilkatStringBuilder;
responseJson: WideString;
json: TChilkatJsonObject;
dtime: TCkDateTime;
bLocalTime: Integer;
dt: IDtObj;

begin
// 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 := TChilkatOAuth2.Create(Self);
oauth2.AccessToken := 'FACEBOOK-ACCESS-TOKEN';

rest := TChilkatRest.Create(Self);

// Connect to Facebook...
success := rest.Connect('graph.facebook.com',443,1,1);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

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

// 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 := TChilkatStringBuilder.Create(Self);
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 <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

json := TChilkatJsonObject.Create(Self);
json.EmitCompact := 0;
json.Load(responseJson);

// Show the JSON in human-readable format.
Memo1.Lines.Add(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.
Memo1.Lines.Add('type: ' + json.StringOf('type'));
Memo1.Lines.Add('message: ' + json.StringOf('message'));
Memo1.Lines.Add('id: ' + json.StringOf('id'));
Memo1.Lines.Add('link: ' + json.StringOf('link'));
Memo1.Lines.Add('privacy descripton: ' + json.StringOf('privacy.description'));

dtime := TCkDateTime.Create(Self);
bLocalTime := 1;
dtime.SetFromTimestamp(json.StringOf('created_time'));
dt := dtime.GetDtObj(bLocalTime);
Memo1.Lines.Add(IntToStr(dt.Month) + '/' + IntToStr(dt.Day) + '/' + IntToStr(dt.Year) + '  ' + IntToStr(dt.Hour)
     + ':' + IntToStr(dt.Minute));
end;