Delphi ActiveX

Download a Binary File into Memory

See more Azure Cloud Storage Examples

Downloads a binary file into memory. 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;
rest: TChilkatRest;
bTls: Integer;
port: Integer;
bAutoReconnect: Integer;
azAuth: TChilkatAuthAzureStorage;
bdFileContents: TChilkatBinData;
sbXmlErr: TChilkatStringBuilder;

begin
success := 0;

// Azure File Service Example: Download a Binary File to Memory
// See:  https://docs.microsoft.com/en-us/rest/api/storageservices/get-file

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

rest := TChilkatRest.Create(Self);

// Connect to the Azure Storage Blob Service
bTls := 1;
port := 443;
bAutoReconnect := 1;
// In this example, the storage account name is "chilkat".
success := rest.Connect('chilkat.file.core.windows.net',port,bTls,bAutoReconnect);
if (success = 0) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// Provide Azure Cloud credentials for the REST calls.
azAuth := TChilkatAuthAzureStorage.Create(Self);
azAuth.AccessKey := 'AZURE_ACCESS_KEY';
// The account name used here should match the 1st part of the domain passed in the call to Connect (above).
azAuth.Account := 'chilkat';
azAuth.Scheme := 'SharedKey';
azAuth.Service := 'File';
// This causes the "x-ms-version: 2021-08-06" header to be automatically added.
azAuth.XMsVersion := '2021-08-06';
success := rest.SetAuthAzureStorage(azAuth.ControlInterface);

// Note: The application does not need to explicitly set the following
// headers: x-ms-date, Authorization.  These headers
// are automatically set by Chilkat.

// Send a GET request to download the file "penguins.jpg" to a BinData object.
// (The share name is "pip")
bdFileContents := TChilkatBinData.Create(Self);
success := rest.FullRequestNoBodyBd('GET','/pip/wildlife/antarctic/penguins.jpg',bdFileContents.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// When successful, the response status will be 200.
// If a non-success status code is returned, then the bdFileContents actually contains the XML error message.
if (rest.ResponseStatusCode <> 200) then
  begin
    // Examine the request/response to see what happened.
    Memo1.Lines.Add('response status code = ' + IntToStr(rest.ResponseStatusCode));
    Memo1.Lines.Add('response status text = ' + rest.ResponseStatusText);
    Memo1.Lines.Add('response header: ' + rest.ResponseHeader);
    sbXmlErr := TChilkatStringBuilder.Create(Self);
    sbXmlErr.AppendBd(bdFileContents.ControlInterface,'utf-8',0,0);
    Memo1.Lines.Add('response body (if any): ' + sbXmlErr.GetAsString());
    Memo1.Lines.Add('---');
    Memo1.Lines.Add('LastRequestStartLine: ' + rest.LastRequestStartLine);
    Memo1.Lines.Add('LastRequestHeader: ' + rest.LastRequestHeader);
    Exit;
  end;

Memo1.Lines.Add('Size of the downloaded file = ' + IntToStr(bdFileContents.NumBytes));

// See the online reference documentation for the BinData class for ways
// to access the bytes.

bdFileContents.WriteFile('qa_output/penguins.jpg');
end;