PdfConverter PDF/A Compliance Guide

This guide shows how to generate PDF/A-compliant output when converting Visio diagram files to PDF using PdfConverter in Aspose.Diagram for .NET. PDF/A is required for long-term archiving and regulatory compliance.

Prerequisites

Aspose.Diagram for .NET (version 26.4.0 or later)
Valid Aspose license applied before calling Process()

Step 1: Configure PDF/A Compliance

Use LowCodePdfSaveOptions with PdfOptions (type PdfSaveOptions) to set the compliance level:

using Aspose.Diagram.LowCode;
using Aspose.Diagram.Saving;

var loadOptions = new LowCodeLoadOptions();
loadOptions.InputFile = "source.vsdx";

var saveOptions = new LowCodePdfSaveOptions();
saveOptions.OutputFile = "output-pdfa.pdf";

var pdfOptions = new PdfSaveOptions();
pdfOptions.Compliance = PdfCompliance.PdfA1b;
saveOptions.PdfOptions = pdfOptions;

PdfConverter.Process(loadOptions, saveOptions);

Step 2: Supported Compliance Levels

The PdfCompliance enum in Aspose.Diagram.Saving provides the following levels:

Value	Description
`PdfCompliance.None`	Standard PDF (default)
`PdfCompliance.PdfA1b`	PDF/A-1b — basic conformance for long-term archiving

Use PdfCompliance.PdfA1b for archival or regulatory requirements.

Step 3: Batch PDF/A Export

Convert multiple Visio files to PDF/A in a loop:

using System.IO;
using Aspose.Diagram.LowCode;
using Aspose.Diagram.Saving;

string inputDir = "diagrams/input";
string outputDir = "diagrams/pdfa-output";
Directory.CreateDirectory(outputDir);

var pdfOptions = new PdfSaveOptions();
pdfOptions.Compliance = PdfCompliance.PdfA1b;

foreach (string file in Directory.GetFiles(inputDir, "*.vsdx"))
{
    string output = Path.Combine(outputDir, Path.GetFileNameWithoutExtension(file) + ".pdf");

    var loadOptions = new LowCodeLoadOptions();
    loadOptions.InputFile = file;

    var saveOptions = new LowCodePdfSaveOptions();
    saveOptions.OutputFile = output;
    saveOptions.PdfOptions = pdfOptions;

    PdfConverter.Process(loadOptions, saveOptions);
    Console.WriteLine($"Exported PDF/A: {Path.GetFileName(output)}");
}

Troubleshooting

Problem	Likely Cause	Fix
Output is not PDF/A-compliant	`PdfOptions` not set before calling `Process()`	Assign `saveOptions.PdfOptions` before the `Process()` call
`NullReferenceException` on Compliance	Accessing unassigned `PdfOptions`	Assign `saveOptions.PdfOptions = new PdfSaveOptions()` before setting `Compliance`
Evaluation watermark in output	License not applied	Apply metered licensing via `metered.SetMeteredKey()` before any `Process()` call