Delphi ActiveX

Google Contacts - Delete a Contact

See more Google APIs Examples

Demonstrates how to delete a Google Contact. Delphi ActiveX

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
success: Integer;
jsonToken: TChilkatJsonObject;
gAuth: TChilkatAuthGoogle;
rest: TChilkatRest;
bAutoReconnect: Integer;
sbPath: TChilkatStringBuilder;
numReplacements: Integer;
sbResponseBody: TChilkatStringBuilder;
xml: TChilkatXml;
lastKnownEtag: WideString;

begin
success := 0;

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

// --------------------------------------------------------------------------------------------------------
// Note: The code for setting up the Chilkat REST object and making the initial connection can be done once.
// Once connected, the REST object may be re-used for many REST API calls.
// (It's a good idea to put the connection setup code in a separate function/subroutine.)
// --------------------------------------------------------------------------------------------------------

// It is assumed we previously obtained an OAuth2 access token.
// This example loads the JSON access token file 
// saved by this example: Get Google Contacts OAuth2 Access Token

jsonToken := TChilkatJsonObject.Create(Self);
success := jsonToken.LoadFile('qa_data/tokens/googleContacts.json');
if (success <> 1) then
  begin
    Memo1.Lines.Add('Failed to load googleContacts.json');
    Exit;
  end;

gAuth := TChilkatAuthGoogle.Create(Self);
gAuth.AccessToken := jsonToken.StringOf('access_token');

rest := TChilkatRest.Create(Self);

// Connect using TLS.
bAutoReconnect := 1;
success := rest.Connect('www.google.com',443,1,bAutoReconnect);

// Provide the authentication credentials (i.e. the access token)
rest.SetAuthGoogle(gAuth.ControlInterface);

// ----------------------------------------------
// OK, the REST connection setup is completed..
// ----------------------------------------------

// To update a contact, we'll first get the contact information
// to get the etag.

// To retrieve the contact, send the following:
// 	GET /m8/feeds/contacts/default/full/{contactId}
// 	GData-Version: 3.0

rest.AddHeader('GData-Version','3.0');

sbPath := TChilkatStringBuilder.Create(Self);
sbPath.Append('/m8/feeds/contacts/default/full/{contactId}');
// Get the contact having contactId = "5b6d64980b1ed462"
numReplacements := sbPath.Replace('{contactId}','5b6d64980b1ed462');

sbResponseBody := TChilkatStringBuilder.Create(Self);
success := rest.FullRequestNoBodySb('GET',sbPath.GetAsString(),sbResponseBody.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// A successful response will have a status code equal to 200.
if (rest.ResponseStatusCode <> 200) then
  begin
    Memo1.Lines.Add('response status code = ' + IntToStr(rest.ResponseStatusCode));
    Memo1.Lines.Add('response status text = ' + rest.ResponseStatusText);
    Memo1.Lines.Add('response header: ' + rest.ResponseHeader);
    Memo1.Lines.Add('response body: ' + sbResponseBody.GetAsString());
    Exit;
  end;

// If the 200 response was received, then the contacts XML is contained
// in the response body.
xml := TChilkatXml.Create(Self);
xml.LoadSb(sbResponseBody.ControlInterface,0);

Memo1.Lines.Add(xml.GetXml());
Memo1.Lines.Add('-------------------');

// Get the etag:
lastKnownEtag := xml.GetAttrValue('gd:etag');
Memo1.Lines.Add('lastKnownEtag = ' + lastKnownEtag);
Memo1.Lines.Add('-------------------');

// To delete, send the following:

// 	DELETE /m8/feeds/contacts/default/full/{contactId}
// 	If-Match: {lastKnownEtag}
// 	GData-Version: 3.0

rest.ClearAllHeaders();
rest.AddHeader('If-Match',lastKnownEtag);
rest.AddHeader('GData-Version','3.0');

// The sbPath already contains the correct path..
success := rest.FullRequestNoBodySb('DELETE',sbPath.GetAsString(),sbResponseBody.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// A successful response will have a status code equal to 200.
if (rest.ResponseStatusCode <> 200) then
  begin
    Memo1.Lines.Add('response status code = ' + IntToStr(rest.ResponseStatusCode));
    Memo1.Lines.Add('response status text = ' + rest.ResponseStatusText);
    Memo1.Lines.Add('response header: ' + rest.ResponseHeader);
    Memo1.Lines.Add('response body: ' + sbResponseBody.GetAsString());
    Memo1.Lines.Add('request header: ' + rest.LastRequestHeader);
    Exit;
  end;

// The response body for a successful DELETE is empty.
Memo1.Lines.Add('Response Body: (should be empty)');
Memo1.Lines.Add(sbResponseBody.GetAsString());
Memo1.Lines.Add('Success.');
end;