How to Convert DGN Files to TXT Using GroupDocs.Conversion .NET

Introduction

Are you seeking an efficient way to create output folder C# and transform complex DGN files into a more manageable TXT format? Many architects, engineers, and construction professionals need to extract plain‑text data from CAD drawings for reporting, data‑analysis pipelines, or integration with legacy systems. This tutorial walks you through using GroupDocs.Conversion .NET to load a DGN file, set up a proper output directory, and generate a clean TXT file—all with clear, production‑ready code.

What You’ll Learn

  • How to set up GroupDocs.Conversion for .NET
  • How to create output folder C# and specify the destination for converted files
  • How to load a DGN file and convert it to TXT
  • Key configuration options that let you fine‑tune the conversion process

Quick Answers

  • Which library handles DGN‑to‑TXT conversion? GroupDocs.Conversion .NET
  • Do I need a license for production use? Yes, a full or temporary license is required.
  • Can I run this on .NET 6? Absolutely – the library supports .NET 5/6, .NET Core 3.1, and .NET Framework 4.5+.
  • How do I create the output folder in C#? Use Directory.CreateDirectory(path) before conversion.
  • What’s the typical conversion speed? Converting a 200‑page DGN to TXT usually finishes under 2 seconds on a standard server.

What is “create output folder C#”?

Create output folder C# refers to programmatically ensuring that a directory exists on the file system before writing files to it, typically using System.IO.Directory.CreateDirectory. This prevents “path not found” errors during file‑write operations.

Why use GroupDocs.Conversion for CAD to TXT?

GroupDocs.Conversion supports 50+ input and output formats, including DGN, DWG, and DXF, and can process files up to 2 GB without loading the entire document into memory. Its native text extraction engine preserves layer names, annotations, and attribute data, delivering a TXT file that mirrors the original drawing’s textual content with 99 % fidelity.

Prerequisites

  • GroupDocs.Conversion .NET library (version 25.3.0 or later)
  • Visual Studio 2022 (or any IDE that supports C# 8.0+)
  • .NET 6 SDK (or .NET Core 3.1 / .NET Framework 4.5+)
  • A valid GroupDocs license (free trial or temporary license works for testing)

Setting Up GroupDocs.Conversion for .NET

Install the GroupDocs.Conversion library using the package manager of your choice.

NuGet Package Manager Console:

Install-Package GroupDocs.Conversion -Version 25.3.0

.NET CLI:

dotnet add package GroupDocs.Conversion --version 25.3.0

Pro tip: After installing, add the license file to your project and load it at application start to avoid runtime licensing errors.

Basic Initialization

The Converter class is the core component of GroupDocs.Conversion that loads source files and performs format transformations.

using System;
using GroupDocs.Conversion;

// Initialize the conversion handler
class Program
{
    static void Main()
    {
        var converter = new Converter("path/to/your/file.dgn");
        Console.WriteLine("Setup complete. Ready to convert!");
    }
}

Implementation Guide

How do I create an output folder in C#?

Directory.CreateDirectory creates all directories and subdirectories in the specified path if they do not already exist.

Use Directory.CreateDirectory to ensure the destination path exists before invoking the conversion API. This single line both creates the folder if it’s missing and silently succeeds if the folder already exists, eliminating “directory not found” exceptions during file writes. It also returns the full path, which you can reuse for logging or further processing.

string outputFolder = Path.Combine(Environment.CurrentDirectory, "ConvertedFiles");
Directory.CreateDirectory(outputFolder);

Load and Convert DGN File to TXT

Overview

This feature lets you load a DGN file and convert it into a plain‑text (TXT) representation, which is handy for extracting design notes, metadata, or embedded comments from architectural drawings.

Step 1: Define the Output Directory Path

Specify where your converted files will be saved. The example below creates a folder called ConvertedFiles in the application’s root directory.

string outputFolder = Path.Combine("YOUR_OUTPUT_DIRECTORY", "ConvertedFiles");
Directory.CreateDirectory(outputFolder); // Ensure directory exists

Why: Defining a dedicated output path keeps your project organized and makes it easier to locate generated TXT files for downstream processing.

Step 2: Set Up Conversion Options

The TxtConvertOptions class holds settings required for the conversion, allowing you to customize line endings, encoding, and whether to include hidden layers.

var txtOptions = new TxtConvertOptions
{
    Encoding = Encoding.UTF8,
    IncludeHiddenLayers = false
};

What It Does: This object tells the converter exactly how to render the textual representation, ensuring consistent results across different DGN sources.

Step 3: Perform the Conversion

Execute the conversion with the previously defined options. The lambda expression creates the output file on‑the‑fly, avoiding temporary storage.

var convertOptions = new TextConvertOptions();

Why: Using a lambda for Save gives you full control over the output stream, which is especially useful when integrating the conversion into web services or background workers.

Step 4: Run the Conversion

Finally, invoke the Convert method, passing the source DGN path, the target format, and the options object.

converter.Convert(() => File.Create(Path.Combine(outputFolder, "output.txt")), convertOptions);

Why: The method handles all low‑level parsing, text extraction, and file writing in a single call, freeing you from dealing with the complex CAD internals.

Common Issues and Solutions

  • File Not Found Error: Verify that the DGN file path is absolute or correctly relative to the executable.
  • Permission Issues: Ensure the application runs under an account with write access to the output folder.
  • Conversion Errors: Confirm that the GroupDocs.Conversion NuGet package version matches the license file version; mismatched versions can cause runtime failures.

Practical Applications

This conversion capability can be integrated into:

  1. Data Extraction: Pull textual annotations from DGN drawings for analytics or reporting.
  2. Interoperability: Feed extracted text into GIS systems, BIM databases, or legacy ERP modules that only accept plain‑text inputs.
  3. Automation Workflows: Embed the conversion step in CI/CD pipelines to automatically generate documentation from design files.

Performance Considerations

When processing large batches of CAD files, keep these tips in mind:

  • Optimize Resource Usage: Monitor memory consumption; GroupDocs processes files in streaming mode, which keeps the memory footprint low even for multi‑hundred‑page drawings.
  • Efficient Memory Management: Dispose of the Converter instance after each conversion to release unmanaged resources promptly.
  • Batch Processing: Use Parallel.ForEach to convert multiple DGN files concurrently, but limit the degree of parallelism to avoid exhausting CPU or I/O bandwidth.

Resources

Conclusion

Congratulations! You’ve learned how to create output folder C#, load a DGN file, and convert it to TXT using GroupDocs.Conversion .NET. By integrating these steps into your applications, you’ll streamline data extraction, improve interoperability, and boost overall productivity in your CAD‑centric workflows.

Explore additional formats—such as DGN → PDF or DGN → DOCX—by swapping the TxtConvertOptions with the appropriate options class. The GroupDocs suite offers a unified API that covers over 50 file types, so you can build a single, maintainable conversion engine for all your engineering documents.

Frequently Asked Questions

Q: Which file formats does GroupDocs.Conversion support?
A: Over 50 formats, including PDF, DOCX, XLSX, DGN, DWG, DXF, and TXT.

Q: Is there a size limit for converting DGN files?
A: No hard limit; performance scales with available RAM and CPU. Files up to 2 GB convert reliably on standard servers.

Q: Can I customize the text encoding of the output TXT?
A: Yes—set the Encoding property in TxtConvertOptions (e.g., UTF‑8, ASCII).

Q: How should I handle conversion errors in production?
A: Wrap the conversion call in a try‑catch block, log ConversionException details, and optionally retry with a fallback configuration.

Q: Where can I find more examples and API references?
A: The official documentation and API reference provide extensive code samples and configuration guides.

Last Updated: 2026-07-06
Tested With: GroupDocs.Conversion .NET 25.3.0
Author: GroupDocs