Delphi ActiveX

Find a Label ID by Name

See more GMail REST API Examples

Lookup the ID of a GMail label by the label name. 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;
http: TChilkatHttp;
userId: WideString;
url: WideString;
sb: TChilkatStringBuilder;
json: TChilkatJsonObject;
jRecord: IChilkatJsonObject;

begin
success := 0;

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

http := TChilkatHttp.Create(Self);
http.AuthToken := 'GMAIL-ACCESS-TOKEN';

userId := 'me';
http.SetUrlVar('userId',userId);

url := 'https://www.googleapis.com/gmail/v1/users/{$userId}/labels';

// Get the list of GMail labels as JSON.
sb := TChilkatStringBuilder.Create(Self);
success := http.QuickGetSb(url,sb.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add(http.LastErrorText);
    Exit;
  end;

json := TChilkatJsonObject.Create(Self);
json.LoadSb(sb.ControlInterface);
json.EmitCompact := 0;
Memo1.Lines.Add(json.Emit());

if (http.LastStatus <> 200) then
  begin
    Memo1.Lines.Add('Failed.');
    Exit;
  end;

// The JSON returned looks like this:
// {
//   "labels": [
//     {
//       "id": "Label_5",
//       "name": "QA",
//       "messageListVisibility": "show",
//       "labelListVisibility": "labelShow",
//       "type": "user"
//     },
//     {
//       "id": "Label_21",
//       "name": "[Gmail]/testFolder",
//       "type": "user"
//     },
//     {
//       "id": "CATEGORY_PERSONAL",
//       "name": "CATEGORY_PERSONAL",
//       "type": "system"
//     },
// 	...

// The name of the label is generally known because it's what we visually see.
// The id is what we need to get.  Assuming the name is unique,
// find the JSON record having name=<desired name>
// For example...
jRecord := json.FindRecord('labels','name','QA',0);
if (json.LastMethodSuccess = 1) then
  begin
    Memo1.Lines.Add('The id of QA is: ' + jRecord.StringOf('id'));

  end;

jRecord := json.FindRecord('labels','name','[Gmail]/testFolder',0);
if (json.LastMethodSuccess = 1) then
  begin
    Memo1.Lines.Add('The id of [Gmail]/testFolder is: ' + jRecord.StringOf('id'));

  end;

jRecord := json.FindRecord('labels','name','questions',0);
if (json.LastMethodSuccess = 1) then
  begin
    Memo1.Lines.Add('The id of questions is: ' + jRecord.StringOf('id'));

  end;

// Output:

// The id of QA is: Label_5
// The id of [Gmail]/testFolder is: Label_21
// The id of questions is: Label_43
end;