DinkToPdf VS PDF.js

I used this package for a while to generate the PDF from HTML - https://github.com/rdvojmoc/DinkToPdf

This may not be applicable in your situation, but I'll leave this info here anyways. I used DinkToPdf https://github.com/rdvojmoc/DinkToPdf for a Blazor Server and a Blazor WASM OMS application. I created a 'Reports' controller, created two different controller action methods. One to create the HTML for the PDF and the other to actually generate the PDF.

The install instructions for DinkToPdf (see github) have a step about installing native binaries that your tutorial seems to be missing.

using Microsoft.Azure.WebJobs; using Microsoft.Azure.WebJobs.Extensions.Http; using Microsoft.Extensions.Logging; using DinkToPdf; using IPdfConverter = DinkToPdf.Contracts.IConverter; using Microsoft.WindowsAzure.Storage; using Microsoft.WindowsAzure.Storage.Blob; using System.Threading.Tasks; namespace Html2Pdf { public class Html2Pdf { // Read more about converter on: https://github.com/rdvojmoc/DinkToPdf // For our purposes we are going to use SynchronizedConverter IPdfConverter pdfConverter = new SynchronizedConverter(new PdfTools()); // A function to convert html content to pdf based on the configuration pased as arguments // Arguments: // HtmlContent: the html content to be converted // Width: the width of the pdf to be created. e.g. "8.5in", "21.59cm" etc. // Height: the height of the pdf to be created. e.g. "11in", "27.94cm" etc. // Margins: the margis around the content // DPI: The dpi is very important when you want to print the pdf. // Returns a byte array of the pdf which can be stored as a file private byte[] BuildPdf(string HtmlContent, string Width, string Height, MarginSettings Margins, int? DPI = 180) { // Call the Convert method of SynchronizedConverter "pdfConverter" return pdfConverter.Convert(new HtmlToPdfDocument() { // Set the html content Objects = { new ObjectSettings { HtmlContent = HtmlContent } }, // Set the configurations GlobalSettings = new GlobalSettings { // PaperKind.A4 can also be used instead of width & height PaperSize = new PechkinPaperSize(Width, Height), DPI = DPI, Margins = Margins } }); } // The name of the function [FunctionName("Html2Pdf")] // The first arugment tells that the functions can be triggerd by a POST HTTP request. // The second argument is mainly used for logging information, warnings or errors public async Task Run([HttpTrigger(AuthorizationLevel.Function, "POST")] Html2PdfRequest Request, ILogger Log) { // PDFByteArray is a byte array of pdf generated from the HtmlContent var PDFByteArray = BuildPdf(Request.HtmlContent, "8.5in", "11in", new MarginSettings(0, 0, 0, 0)); // The connection string of the Storage Account to which our PDF file will be uploaded // The connection string of the Storage Account to which our PDF file will be uploaded var StorageConnectionString = "DefaultEndpointsProtocol=https;AccountName=;AccountKey=;EndpointSuffix=core.windows.net"; // Generate an instance of CloudStorageAccount by parsing the connection string var StorageAccount = CloudStorageAccount.Parse(StorageConnectionString); // Create an instance of CloudBlobClient to connect to our storage account CloudBlobClient BlobClient = StorageAccount.CreateCloudBlobClient(); // Get the instance of CloudBlobContainer which points to a container name "pdf" // Replace your own container name CloudBlobContainer BlobContainer = BlobClient.GetContainerReference("pdf"); // Get the instance of the CloudBlockBlob to which the PDFByteArray will be uploaded CloudBlockBlob Blob = BlobContainer.GetBlockBlobReference(Request.PDFFileName); // Upload the pdf blob await Blob.UploadFromByteArrayAsync(PDFByteArray, 0, PDFByteArray.Length); } } }

I first started building the app in the browser, using PDF.js and Download.js to take a PDF and edit it, and then download it to your computer.

pdf2json is a module that transforms PDF files from binary to JSON format, using pdf.js for its core functionality. It also incorporates support for interactive form elements, enhancing its utility in processing and interpreting PDF content.

Why not PDF.js?

I'd think opening a PDF in your browser would be at the same risk-level you associate with going to any random URL. On Firefox at least, I'm pretty sure the built-in PDF viewer is simply JS parsing and rendering the PDF anyway -- nothing with elevated permissions:

https://mozilla.github.io/pdf.js/

The PDF features are actually an extension, just one built in as Firefox's default pdf viewer.

It's called pdf.js https://github.com/mozilla/pdf.js/

You can actually use this pdf viewer in another browser like Chrome if you'd like, there's a demo URL on there.

We use Mozilla's PDF.js via the pdfjs-dist NPM module to load pages from a PDF file. The loadPdfPages function reads the PDF file and extracts its content. It returns an array where each object contains the page number and the text of that page.

The problem is that there simply wasn't a better option at the time.

Ogg Vorbis was a novelty at best, and it was the only decently widely adopted open source competitor for any of the items listed that was available at the time.

HTML5 was only just published when Chrome launched. So Flash was at that point the only option available to show a video in the browser (sure, downloading a RealPlayer file was always an option, but it was clunky, creators didn't like people being able to save stuff locally, and was also not open source). Chrome in fact arguably accelerated the process of getting web video open sourced: Google bought On2 in 2010 to get the rights to VP8 (the only decent H.264 competitor available at that point) so they could immediately open source it. The plan was in fact to remove H.264 from Chrome entirely once VP8/VP9 adoption ramped up[1], but that didn’t end up happening.

Flash was integrated into Chrome because people were going to use it anyway, and having Google distribute it at least let them both sandbox it and roll out automatic updates (a massive vector for malware at the time was ads pretending to be Flash updates, which worked because people were just that used to constant Flash security patches, most of which required a full reboot to apply; Chrome fixed both of those issues). Apple are the ones who ultimately dealt the death blow to Flash, and it was really just because Adobe could not optimize it for phone CPUs no matter what they tried (even the few Android releases of Flash that we got were practically unusable). That also further accelerated the adoption of open source HTML5 technologies.

PDF is an open source format, and has been since 2008. While I don't know if pressure from Google is what did it, that wouldn’t surprise me. Regardless, the Chrome PDF reader, PDFium, is open source[2] and Mozilla's equivalent project from 2011, PDF.js, is also open source.[3] Both of these projects replaced the distinctly closed source Adobe Reader plugin that was formerly mandatory for viewing PDFs in the browser.

Chrome is directly responsible for eliminating a lot of proprietary software from mainstream use and replacing it with high-quality open source tools. While they've caused problems in other areas of browser development that are worthy of criticism, Chrome's track record when it comes to open sourcing their tech has been very good.

[1]: https://blog.chromium.org/2011/01/html-video-codec-support-i...

[2]: https://github.com/chromium/pdfium

[3]: https://github.com/mozilla/pdf.js

Firefox Nightly is an unstable test version. You should report PDF issues to this GitHub repository.

Open this page and click on New Issue to ask the developers of the PDF viewer: mozilla/pdf.js repository. Please post a link to your question here.