Save PDF file to One Drive

9 Aug 20237 minutes to read

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

Step 1 Create the Microsoft graph API.

Need to create a Microsoft Graph API application and obtain the necessary credentials, namely the application ID and tenant ID. Follow the steps provided in the link to create the application and obtain the required IDs.

Step 2: Create a PDF Viewer sample in Angular

Follow the instructions provided in this link to create a simple PDF Viewer sample in Angular. This will set up the basic structure of your PDF Viewer application.

Step 3: Modify the PdfViewerController.cs File in the Web Service Project

1. Create a web service project in .NET Core 3.0 or above. You can refer to this link for instructions on how to create a web service project.

2. Open the PdfViewerController.cs file in your web service project.

3. Import the required namespaces at the top of the file:

using System.IO;
using Microsoft.Graph;
using Microsoft.Identity.Client;
using Helpers;

1. Add the following private fields and constructor parameters to the PdfViewerController class, In the constructor, assign the values from the configuration to the corresponding fields

private IConfiguration _configuration;
public readonly string folderName;
public readonly string applicationId;
public readonly string tenantId;

public PdfViewerController(IWebHostEnvironment hostingEnvironment, IMemoryCache cache, IConfiguration configuration)
{
  _hostingEnvironment = hostingEnvironment;
  _cache = cache;
  _configuration = configuration;
  folderName = _configuration.GetValue<string>("FolderName");
  tenantId = _configuration.GetValue<string>("TenantId");
  applicationId = _configuration.GetValue<string>("ApplicationId");
}

1. Modify the Download() method to save the downloaded PDF files to One Drive bucket

[HttpPost("Download")]
[Microsoft.AspNetCore.Cors.EnableCors("MyPolicy")]
[Route("[controller]/Download")]
//Post action for downloading the PDF documents

public async Task<IActionResult> Download([FromBody] Dictionary<string, string> jsonObject)
{
  //Initialize the PDF Viewer object with memory cache object
  PdfRenderer pdfviewer = new PdfRenderer(_cache);
  string documentBase = pdfviewer.GetDocumentAsBase64(jsonObject);
  byte[] documentBytes = Convert.FromBase64String(documentBase.Split(",")[1]);

  // Save the PDF as a stream
  Stream stream = new MemoryStream(documentBytes);

  string documentId = jsonObject["documentId"];
  string result = Path.GetFileNameWithoutExtension(documentId);
  string fileName = result + "_downloaded.pdf";

  var config = LoadAppSettings();
  var client = GetAuthenticatedGraphClient(config);

  var request = client.Me.Drive.Root.Children.Request();
  string folderId = string.Empty;
  var results = await request.GetAsync();

  var folder = results.FirstOrDefault(f => f.Name == folderName && f.Folder != null);
  if (folder != null)
  {
    // Save the matching folderId
    folderId = folder.Id;
  }

  var uploadedFile = client.Me.Drive.Items[folderId]
                     .ItemWithPath(fileName)
                     .Content
                     .Request()
                     .PutAsync<DriveItem>(stream)
                     .Result;

  return Content(documentBase);
}

1. Open the appsettings.json file in your web service project, Add the following lines below the existing "AllowedHosts" configuration

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  },
  "AllowedHosts": "*",
  "TenantId": "Your_Tenant_ID",
  "applApplicationIdicationId": "Your_Application_ID",
  "FolderName": "Your_Folder_Name_To_Access_The_Files_In_Onedrive"
}

NOTE

Replace Your_Tenent_ID, Your_Application_ID, and Your_Folder_Name_To_Access_The_Files_In_Onedrive with your actual tenant ID, application ID, and folder name.

Step 4: Set the PDF Viewer Properties in Angular PDF viewer component

Modify the serviceUrl property of the PDF viewer component with the accurate URL of your web service project, replacing https://localhost:44396/pdfviewer with the actual URL of your server. Set the documentPath property of the PDF viewer component to the desired name of the PDF file you wish to load from One Drive. Ensure that you correctly pass the document name from the files available in your drive folder to the documentPath property.

import { Component, OnInit } from '@angular/core';
import { LinkAnnotationService, BookmarkViewService, MagnificationService,
         ThumbnailViewService, ToolbarService, NavigationService,
         TextSearchService, AnnotationService, TextSelectionService,
         PrintService, FormDesignerService, FormFieldsService} from '@syncfusion/ej2-angular-pdfviewer';

@Component({
  selector: 'app-container',
  // specifies the template string for the PDF Viewer component
  template: `<div class="content-wrapper">
                  <ejs-pdfviewer id="pdfViewer"
                                [serviceUrl]='service'
                                [documentPath]='documentPath'
                                style="height:640px;display:block">
                  </ejs-pdfviewer>
            </div>`,
  providers: [ LinkAnnotationService, BookmarkViewService, MagnificationService,ThumbnailViewService, 
               ToolbarService, NavigationService, AnnotationService, TextSearchService,
                TextSelectionService, PrintService, FormDesignerService, FormFieldsService]
  })
  export class AppComponent implements OnInit {
    // Replace the "localhost:44396" with the actual URL of your server
    public service = 'https://localhost:44396/pdfviewer';
    public documentPath = 'PDF_Succinctly.pdf';
  }

NOTE

The following NuGet packages are required to use the previous code example

• Microsoft.Identity.Client
• Microsoft.Graph
• Microsoft.Extensions.Configuration
• Microsoft.Extensions.Configuration.FileExtensions
• Microsoft.Extensions.Configuration.Json

You can install these packages using the NuGet Package Manager.

View sample in GitHub