Delphi DLL

Get Individual Photo Info

See more Facebook Examples

Assuming we have the ID of a Photo, this example demonstrates how to retrieve the photo information and parse the JSON. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, OAuth2, Rest, StringBuilder, JsonObject;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
oauth2: HCkOAuth2;
rest: HCkRest;
photoId: PWideChar;
sbPath: HCkStringBuilder;
responseJson: PWideChar;
json: HCkJsonObject;
canDelete: Boolean;
height: Integer;
width: Integer;

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 := 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);

// Assumes we've already obtained a Photo ID.
photoId := '10210199026347451';

sbPath := CkStringBuilder_Create();
CkStringBuilder_Append(sbPath,'/v2.7/');
CkStringBuilder_Append(sbPath,photoId);

// Select the fields we want.
// This example will select many of the possible fields.
// See https://developers.facebook.com/docs/graph-api/reference/photo/
CkRest_AddQueryParam(rest,'fields','id,album,can_delete,can_tag,from,height,width,images,link,name,name_tags,picture,place,target');

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 response is shown below.
// Demonstrate how to parse values from the JSON.
Memo1.Lines.Add('Album name: ' + CkJsonObject__stringOf(json,'album.name'));
canDelete := CkJsonObject_BoolOf(json,'can_delete');
Memo1.Lines.Add('Can Delete: ' + IntToStr(Ord(canDelete)));
Memo1.Lines.Add('From Name: ' + CkJsonObject__stringOf(json,'from.name'));
height := CkJsonObject_IntOf(json,'height');
width := CkJsonObject_IntOf(json,'width');
Memo1.Lines.Add('Dimensions: ' + IntToStr(width) + 'x' + IntToStr(height));
Memo1.Lines.Add('First Image Source: ' + CkJsonObject__stringOf(json,'images[0].source'));

// A sample JSON response is shown here.  
// { 
//   "id": "10210199026347451",
//   "album": { 
//     "created_time": "2009-10-19T00:06:46+0000",
//     "name": "Timeline Photos",
//     "id": "1237223526054"
//   },
//   "can_delete": true,
//   "can_tag": true,
//   "from": { 
//     "name": "Matt Smith",
//     "id": "10224048320139890"
//   },
//   "height": 120,
//   "width": 120,
//   "images": [
//     { 
//       "height": 120,
//       "source": "https:\/\/scontent.xx.fbcdn.net\/v\/t1.0-9\/14462791_10210199026347451_7830642117574407060_n.jpg?oh=a7f9ed10cf9cd81a82adeb541c60e2e2&oe=58ABB195",
//       "width": 120
//     }
//   ],
//   "link": "https:\/\/www.facebook.com\/photo.php?fbid=10210199026347451&set=a.1237223526054.2038240.1093202869&type=3",
//   "name": "Ignore my posts -- I'm doing some testing for Facebook related programming...",
//   "picture": "https:\/\/scontent.xx.fbcdn.net\/v\/t1.0-9\/14462791_10210199026347451_7830642117574407060_n.jpg?oh=a7f9ed10cf9cd81a82adeb541c60e2e2&oe=58ABB195"
// }
// 

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

end;