File.ViewFromStream in AL: Display Text Directly from Stream

Microsoft Dynamics 365 Business Central 2025 Wave 1 continues to improve its developer experience with handy new features. One of the exciting additions in this release is the File.ViewFromStream method — a simple yet powerful function that enhances how developers interact with files stored in memory.

In the current versions of Business Central, when you need to view an attached document, a report output, or an incoming file, the typical process involves downloading the file first and then opening it with an external application. This can be time-consuming, especially when dealing with multiple files or when you simply need a quick glance at the content. Switching between applications disrupts your workflow and can feel inefficient.

📘 What is File.ViewFromStream?

The new method File.ViewFromStream(Stream: InStream,Text[,Boolean]) enables developers to open or preview a file directly from a stream, without having to save it to a temporary physical file.

This is a major convenience when working with files generated on the fly — such as PDFs, Excel files, or text reports — especially in scenarios where users just need to view or download the file rather than save it on the server.

Syntax

[Ok := ]  File.ViewFromStream(InStream: InStream, FileName: Text [, AllowDownloadAndPrint: Boolean])

🛠 Example:

procedure ShowGeneratedReport()
var
    TempBlob: Codeunit "Temp Blob";
    OutStream: OutStream;
    InStream: InStream;
    ReportContent: Text;
begin
    ReportContent := 'Hello from AL!' + Format(CurrentDateTime) + '\nThis is a preview of your text report.';

    TempBlob.CreateOutStream(OutStream);
    OutStream.WriteText(ReportContent);

    TempBlob.CreateInStream(InStream);
    File.ViewFromStream(InStream, 'ReportPreview.txt', true);
end;

💼 Use Cases

Here are some scenarios where ViewFromStream can be a game-changer:

  • Previewing customer invoices or sales reports generated on-demand.
  • Opening files attached in workflow approvals.
  • On-the-fly document generation in extensions or apps.

The File.ViewFromStream method offers a powerful and user-friendly way to present stream content directly within Dynamics 365 Business Central. The File.ViewFromStream method is a lightweight, client-friendly way to present text content on the fly in Business Central.

Stay tuned for more.

Preview PDFs Directly in Business Central Web Client (v26)

With the release of version 26, a significant productivity boost has arrived: direct PDF attachment previews within the web client. No more downloading, opening external viewers, or switching between applications. This streamlined experience lets you access and review crucial documents instantly, right within your Business Central workflow.

What Does This Mean For You?

Imagine you’re processing a purchase order and need to quickly verify the attached vendor invoice. Previously, you’d have to download the PDF, open it in a separate application, and then return to Business Central. This process was time-consuming and disruptive.

Now, with the new preview functionality, you can:

  • View PDFs directly in the FactBox: When a PDF is attached to a record (like a sales order, purchase invoice, or customer card), you can preview it instantly in the FactBox without leaving the page.
  • Save time and improve efficiency: Eliminate the need for downloads and external viewers, allowing you to focus on your core tasks.
  • Enhance collaboration: Quickly share and review documents with colleagues, streamlining approvals and decision-making.
  • Enjoy a seamless user experience: The integrated preview functionality provides a more intuitive and efficient workflow.

How Does It Work?

The new feature leverages the browser’s built-in PDF rendering capabilities. When you click on a PDF attachment in the FactBox, the document opens directly within the Business Central web client, allowing you to:

  • Scroll through pages.
  • Zoom in and out.
  • Search for specific text.

This feature is enabled by default in Business Central version 26. Simply open a record with a PDF attachment, and you’ll see the preview option in the FactBox.

For Developers:

  • Microsoft has added the following AL methods to enable this functionality.
    • File.ViewFromStream (for Business Central online)
    • File.View (for Business Central on-premises)