Save PDF file to Google Drive

12 Jan 20245 minutes to read

To save a PDF file to Google Drive, you can follow the steps below

Step 1 Set up Google Drive API

You must set up a project in the Google Developers Console and enable the Google Drive API. Obtain the necessary credentials to access the API. For more information, view the official link.

Step 2: Create a Simple SfPdfViewer Sample in blazor

Start by following the steps provided in this link to create a simple SfPdfViewer sample in blazor. This will give you a basic setup of the SfPdfViewer component.

Step 3: Include the following namespaces in the Index.razor file.

  1. Import the required namespaces at the top of the file:
@using Google.Apis.Drive.v3;
@using Google.Apis.Auth.OAuth2;
@using Google.Apis.Services;
@using Google.Apis.Util.Store;
@using System.Threading.Tasks;
@using Syncfusion.Blazor.SfPdfViewer;
@using Syncfusion.Blazor.Buttons

Step 4: Add the below code example to save the downloaded PDF files to Google drive file.

@page "/"
<SfButton @onclick="OnClick">Save file to google drive</SfButton>

<SfPdfViewer2 DocumentPath="@DocumentPath"
              @ref="@viewer"
              Height="100%"
              Width="100%">
</SfPdfViewer2>

@code {
    private string DocumentPath { get; set; }
    private SfPdfViewer2 viewer;
    private readonly string FolderId = "Your Google Drive Folder ID";
    private readonly string CredentialPath = "Your Path to the OAuth 2.0 Client IDs json file";
    private readonly string ApplicationName = "Your Application name";
    private readonly string FileName = "File Name to be loaded into Syncfusion SfPdfViewer";
    private static readonly string[] Scopes = { DriveService.Scope.DriveFile, DriveService.Scope.DriveReadonly };

    public async void OnClick(MouseEventArgs args)
    {
        byte[] data = await viewer.GetDocumentAsync();
        string result = Path.GetFileNameWithoutExtension(FileName);
        string fileName = result + "_downloaded.pdf";
        UserCredential credential;

        using (var memStream = new FileStream(CredentialPath, FileMode.Open, FileAccess.Read))
        {
            string credPath = "token.json";
            credential = await GoogleWebAuthorizationBroker.AuthorizeAsync(
            GoogleClientSecrets.Load(memStream).Secrets,
            Scopes,
            "user",
             CancellationToken.None,
            new FileDataStore(credPath, true));
        }

        // Create the Drive API service.
        var service = new DriveService(new BaseClientService.Initializer()
            {
                HttpClientInitializer = credential,
                ApplicationName = ApplicationName,
            });

        var fileMetadata = new Google.Apis.Drive.v3.Data.File()
            {
                Name = fileName,
                Parents = new List<string> { FolderId }
            };

        FilesResource.CreateMediaUpload request;

        using (var stream = new MemoryStream(data))
        {
            request = service.Files.Create(fileMetadata, stream, "application/pdf");
            request.Fields = "id";
            object value = await request.UploadAsync();
        }
    }
}

NOTE

Replace Your Google Drive Folder ID with your actual Google Drive folder ID, Your Application name with your actual application name, File Name to be Loaded into Syncfusion SfPdfViewer with the actual file name you want to load from the Azure container to the Syncfusion SfPdfViewer and Your Path to the OAuth 2.0 Client IDs JSON file with the actual path to your OAuth 2.0 Client IDs JSON file

NOTE

The FolderId part is the unique identifier for the folder. For example, if your folder URL is: https://drive.google.com/drive/folders/abc123xyz456, then the folder ID is abc123xyz456.

NOTE

The Google.Apis.Drive.v3 NuGet package must be installed in your application to use the previous code example.

View sample in GitHub