Extract PNG preview image from active configuration using SOLIDWORKS Document Manager API

Example demonstrates how to extract PNG preview image from the active configuration of SOLIDWORKS assembly or part using the document manager API.

This approach would work for both in-process and out-of-process application.

Create C# Console application
Paste the code
Run the application with 2 arguments: full path to the input SOLIDWORKS part or assembly and full path to output PNG image

This example is using the ISwDMConfiguration9::GetPreviewPNGBitmapBytes SOLIDWORKS Document Manager API to extract byte buffer of preview and convert it to an Image object.

using SwDocumentMgr;
using System;
using System.Drawing;
using System.IO;

namespace CodeStackExample
{
    class Program
    {
        const string LICENSE_KEY = "[Document Manager License Key]";

        static void Main(string[] args)
        {
            var filePath = args[0];
            var outImgFilePath = args[1];

            var classFact = new SwDMClassFactory();

            var app = classFact.GetApplication(LICENSE_KEY);

            var docType = SwDmDocumentType.swDmDocumentUnknown;

            switch (Path.GetExtension(filePath).ToLower())
            {
                case ".sldprt":
                    docType = SwDmDocumentType.swDmDocumentPart;
                    break;

                case ".sldasm":
                    docType = SwDmDocumentType.swDmDocumentAssembly;
                    break;

                case ".slddrw":
                    docType = SwDmDocumentType.swDmDocumentDrawing;
                    break;
            }

            SwDmDocumentOpenError err;
            var doc = app.GetDocument(filePath, docType, true, out err);

            if (doc != null)
            {
                var activeConfName = doc.ConfigurationManager.GetActiveConfigurationName();

                var conf = doc.ConfigurationManager.GetConfigurationByName(activeConfName) as ISwDMConfiguration14;

                SwDmPreviewError previewErr;
                var imgBytes = conf.GetPreviewPNGBitmapBytes(out previewErr) as byte[];

                if (previewErr == SwDmPreviewError.swDmPreviewErrorNone)
                {
                    using (var memStr = new MemoryStream(imgBytes))
                    {
                        memStr.Seek(0, SeekOrigin.Begin);
                        var img = Image.FromStream(memStr);
                        img.Save(outImgFilePath);
                    }
                }
                else
                {
                    Console.WriteLine($"Failed to extract preview from the document: {previewErr}");
                }
            }
            else
            {
                Console.WriteLine($"Failed to open the document: {err}");
            }
        }
    }
}