(Delphi DLL) 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 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, CkDateTime, DtObj, OAuth2, StringBuilder, JsonObject, Rest;

...

procedure TForm1.Button1Click(Sender: TObject);
var
oauth2: HCkOAuth2;
rest: HCkRest;
success: Boolean;
postId: PWideChar;
sbPath: HCkStringBuilder;
responseJson: PWideChar;
json: HCkJsonObject;
dtime: HCkDateTime;
bLocalTime: Boolean;
dt: HCkDtObj;

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 := CkOAuth2_Create();
CkOAuth2_putAccessToken(oauth2,'FACEBOOK-ACCESS-TOKEN');

rest := CkRest_Create();

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

// Provide the authentication credentials (i.e. the access key)
CkRest_SetAuthOAuth2(rest,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 := CkStringBuilder_Create();
CkStringBuilder_Append(sbPath,'/v2.7/');
CkStringBuilder_Append(sbPath,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/
CkRest_AddQueryParam(rest,'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 := CkRest__fullRequestNoBody(rest,'GET',CkStringBuilder__getAsString(sbPath));
if (CkRest_getLastMethodSuccess(rest) <> True) then
  begin
    Memo1.Lines.Add(CkRest__lastErrorText(rest));
    Exit;
  end;

json := CkJsonObject_Create();
CkJsonObject_putEmitCompact(json,False);
CkJsonObject_Load(json,responseJson);

// Show the JSON in human-readable format.
Memo1.Lines.Add(CkJsonObject__emit(json));

// 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: ' + CkJsonObject__stringOf(json,'type'));
Memo1.Lines.Add('message: ' + CkJsonObject__stringOf(json,'message'));
Memo1.Lines.Add('id: ' + CkJsonObject__stringOf(json,'id'));
Memo1.Lines.Add('link: ' + CkJsonObject__stringOf(json,'link'));
Memo1.Lines.Add('privacy descripton: ' + CkJsonObject__stringOf(json,'privacy.description'));

dtime := CkDateTime_Create();
bLocalTime := True;
CkDateTime_SetFromTimestamp(dtime,CkJsonObject__stringOf(json,'created_time'));
dt := CkDateTime_GetDtObj(dtime,bLocalTime);
Memo1.Lines.Add(IntToStr(CkDtObj_getMonth(dt)) + '/' + IntToStr(CkDtObj_getDay(dt)) + '/' + IntToStr(CkDtObj_getYear(dt)) + '  '
     + IntToStr(CkDtObj_getHour(dt)) + ':' + IntToStr(CkDtObj_getMinute(dt)));
CkDtObj_Dispose(dt);

CkOAuth2_Dispose(oauth2);
CkRest_Dispose(rest);
CkStringBuilder_Dispose(sbPath);
CkJsonObject_Dispose(json);
CkDateTime_Dispose(dtime);

end;