(Delphi ActiveX) OneDrive -- List Large Directory

See more OneDrive Examples

Note: This example requires Chilkat v9.5.0.97 or greater.

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
json: TChilkatJsonObject;
http: TChilkatHttp;
resp: WideString;
i: Integer;
numItems: Integer;
bGetMore: Integer;
nextLink: WideString;

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

// This example uses the OAuth client credentials flow.
// See How to Create an Azure App Registration for OAuth 2.0 Client Credentials

// Use your client ID, client secret, and tenant ID in the following lines
json := TChilkatJsonObject.Create(Self);
json.UpdateString('client_id','2871da2c-8176-4b7f-869b-2311aa82e743');
json.UpdateString('client_secret','2hu9Q~r5QuryUcEkNbg1btLtnfU1VUXzhSCG6brH');
json.UpdateString('scope','https://graph.microsoft.com/.default');
json.UpdateString('token_endpoint','https://login.microsoftonline.com/114d7ed6-71bf-4dbe-a866-748364121bf2/oauth2/v2.0/token');

http := TChilkatHttp.Create(Self);
http.AuthToken := json.Emit();

// This example will get the DriveItems in /lots-of-files, which has 450 children..
http.SetUrlVar('item_path','/lots-of-files');
http.SetUrlVar('user_id','4fe732c3-322e-4a6b-b729-2fd1eb5c6104');

json.EmitCompact := 0;

// This loop will download DriveItems in sets of 25 until no more exist.
bGetMore := 1;
// (Add the $top query parameter to define the page size, i.e. the max number of results to return).
nextLink := 'https://graph.microsoft.com/v1.0/users/{$user_id}/drive/root:{$item_path}:/children?$top=25';

while (bGetMore = 1) do
  begin

    // Get the next chunk of DriveItems
    resp := http.QuickGetStr(nextLink);
    if (http.LastMethodSuccess <> 1) then
      begin
        Memo1.Lines.Add(http.LastErrorText);
        Exit;
      end;

    // The response should be JSON.
    json.Load(resp);

    // A successful response should return a status code of 200.
    if (http.LastStatus <> 200) then
      begin
        Memo1.Lines.Add(json.Emit());
        Memo1.Lines.Add('Response status = ' + IntToStr(http.LastStatus));
        Exit;
      end;

    // Iterate over the DriveItems in the JSON response:
    i := 0;
    numItems := json.SizeOfArray('value');
    while i < numItems do
      begin
        json.I := i;
        Memo1.Lines.Add('name: ' + json.StringOf('value[i].name'));
        i := i + 1;
      end;

    // If a nextLink was included in the JSON, use it to get the next set of 50 DriveItems.
    // Otherwise, exit the loop.
    if (json.HasMember('"@odata.nextLink"') = 1) then
      begin
        nextLink := json.StringOf('"@odata.nextLink"');
        Memo1.Lines.Add('nextLink: ' + nextLink);
      end
    else
      begin
        bGetMore := 0;
      end;
  end;
end;