PDFFlatten 0.2.0

PDFFlatten

PDFFlatten is a small C# / .NET Standard 2.0 utility library for turning interactive AcroForm PDFs into plain, printable page content.

The library target stays at netstandard2.0 so the same package can be consumed from .NET Framework 4.6.1+ (including 4.6.2) and current .NET releases.

Why this package exists

Some PDFs print badly from mobile devices or lightweight viewers because the form fields remain interactive. PDFFlatten converts those widget appearances into ordinary page content so the rendered values travel with the page.

Features

• netstandard2.0 package for broad reuse
• simple PdfFlattener.Flatten(Stream) API
• overload for caller-owned output streams
• in-house flattening implementation with no restrictive third-party PDF dependency
• C# library source with one class per file and XML docs on the public surface
• generic-fixture and synthetic regression tests targeting net10.0
• NuGet package metadata, XML docs, symbols, SourceLink, and MIT licence
• GitHub Actions for CI, packaging, and tagged releases

Install

dotnet add package PDFFlatten

Compatibility posture

• Library target: netstandard2.0
• Consumer reach: designed for .NET Framework 4.6.2+ and current .NET runtimes through the .NET Standard 2.0 surface area
• Repo validation target: the sample app, tests, and CI currently run on net10.0 as the repo's latest-SDK smoke-test lane; that does not change the package target or consumer matrix
• Source layout: C# implementation with one class per file, with public API kept intentionally small

Quick start — modern .NET / C#

using PDFFlatten;
using System.IO;

using Stream input = File.OpenRead("input.pdf");
using Stream flattened = PdfFlattener.Flatten(input);
using Stream output = File.Create("flattened.pdf");
flattened.CopyTo(output);

If you already manage the destination stream:

using PDFFlatten;
using System.IO;

using Stream input = File.OpenRead("input.pdf");
using Stream output = File.Create("flattened.pdf");
PdfFlattener.Flatten(input, output);

Quick start — VB.NET on .NET Framework 4.6.2

Imports PDFFlatten
Imports System.IO

Using input As Stream = File.OpenRead("input.pdf")
    Using flattened As Stream = PdfFlattener.Flatten(input)
        Using output As Stream = File.Create("flattened.pdf")
            flattened.CopyTo(output)
        End Using
    End Using
End Using

Caller-owned output stream example:

Imports PDFFlatten
Imports System.IO

Using input As Stream = File.OpenRead("input.pdf")
    Using output As Stream = File.Create("flattened.pdf")
        PdfFlattener.Flatten(input, output)
    End Using
End Using

Console sample

A minimal C# console app lives in samples/PDFFlatten.Sample for local CLI testing on macOS, Linux, or Windows.

dotnet run --project samples/PDFFlatten.Sample -- GenericAcroFormFixture.pdf GenericAcroFormFixture.flattened.pdf

The sample targets net10.0 so local smoke tests run on the current SDK, while the reusable package remains netstandard2.0 for consumer reach.

Supported scope in v0.1

PDFFlatten currently targets a practical first slice:

• classic cross-reference-table PDFs
• AcroForm widget annotations with normal appearance streams (/AP /N)
• flattening by replaying those appearance streams onto the page content

That covers the included synthetic AcroForm fixture and keeps the public API stable while the engine grows.

Project layout

PDFFlatten.sln
src/
  PDFFlatten/
    PDFFlatten.csproj
    PdfFlattener.cs
    Internals/        # one class per file for internal model/parser/serializer types
samples/
  PDFFlatten.Sample/
    Program.cs
tests/
  PDFFlatten.Tests/
docs/
  github-setup.md
CHANGELOG.md
CONTRIBUTING.md

Build, test, and pack locally

dotnet restore
dotnet build PDFFlatten.sln --configuration Release
dotnet test PDFFlatten.sln --configuration Release
dotnet pack src/PDFFlatten/PDFFlatten.csproj --configuration Release --output artifacts

Release flow

1. Update CHANGELOG.md.
2. Commit and push to GitHub.
3. Create a version tag like v0.2.0.
4. Push the tag.
5. GitHub Actions builds, tests, packs, creates a GitHub release, and publishes to NuGet.

git tag v0.2.0
git push origin v0.2.0

GitHub setup

Use the full walkthrough in docs/github-setup.md.

In short, you need to:

1. create the GitHub repo
2. push main
3. add the NUGET_API_KEY repository secret
4. enable Actions
5. tag releases with v*

CI/CD included

• CI: restore, build, test, pack validation
• Release: build, test, pack, GitHub release, NuGet publish

Contributing and maintenance

• contribution guide: CONTRIBUTING.md
• release notes scaffold: CHANGELOG.md
• GitHub bootstrap guide: docs/github-setup.md

Notes

• Caller-owned streams are left open.
• The synthetic PDF fixture is covered by automated tests.
• If you publish under a different GitHub owner/repo, update the package metadata URLs in src/PDFFlatten/PDFFlatten.csproj.