Get thumbnail of any file including SolidWorks on

问题:

There is a lot of build-in ThumbnailProviders inside every installed OS. Due to these providers Windows is able to show Thumbnail of many files. For example Windows Explorer can show content of *.jpg files, but from Solidworks *.sldprt files too (If SolidWorks is installed).

But is there any way to get these thumbnails? I´ve tried to manage this using Windows API CodecPack, but I succeeded only on Windows 7.

ShellFile shellFile = ShellFile.FromFilePath(filePath);                
Bitmap shellThumb = shellFile.Thumbnail.Bitmap;

Question is: is there any other usable way to get Thumbnail of any file with registered Thumbnail provider on Windows XP/Vista? I´m really desperate...

回答1:

There are several ways:

1) With library OpenMCDF. Solidworks file is Compound document so access to its content - is parsing the file.

 OpenFileDialog dialog = new OpenFileDialog();    
 dialog.InitialDirectory = Application.StartupPath;  
 if (dialog.ShowDialog() == DialogResult.OK)  
 {  
     string STORAGE_NAME = dialog.FileName.ToString();  
     CompoundFile cf = new CompoundFile(STORAGE_NAME);  
     CFStream st = cf.RootStorage.GetStream("PreviewPNG");  
     byte[] buffer = st.GetData();  
     var ms = new MemoryStream(buffer.ToArray());  
     pictureBox1.Image = Image.FromStream(ms);  
  }  

2) With library EModelView.dll to be added as a control and placed to the Form.

    OpenFileDialog dialog = new OpenFileDialog();
        if (dialog.ShowDialog() == DialogResult.OK)
        {
            axEModelViewControl1.OpenDoc(dialog.FileName.ToString(), false, false, true, "");
        }

3) With SWExplorer library (wpfPreviewFlowControl)

        OpenFileDialog dialog = new OpenFileDialog();
        if (dialog.ShowDialog() == DialogResult.OK)
        {
            string sDocFileName = dialog.FileName.ToString();
            wpfThumbnailCreator pvf;
            pvf = new wpfThumbnailCreator();
            System.Drawing.Size size = new Size();
            size.Width = 200;
            size.Height = 200;
            pvf.DesiredSize = size;
            System.Drawing.Bitmap pic = pvf.GetThumbNail(sDocFileName);
            pictureBox1.Image = pic;
        }

3) With library Document Manager (SolidWorks.Interop.swdocumentmgr)

         OpenFileDialog dialog = new OpenFileDialog();
        if (dialog.ShowDialog() == DialogResult.OK)
        {
            string sDocFileName = dialog.FileName.ToString();
            SwDMClassFactory swClassFact = default(SwDMClassFactory);
            SwDMApplication swDocMgr = default(SwDMApplication);
            SwDMDocument swDoc = default(SwDMDocument);
            SwDMConfigurationMgr swCfgMgr = default(SwDMConfigurationMgr);
            string[] vCfgNameArr = null;
            SwDMConfiguration7 swCfg = default(SwDMConfiguration7);
            IPictureDisp pPreview = default(IPictureDisp);
            SwDmDocumentType nDocType = 0;
            SwDmDocumentOpenError nRetVal = 0;
            SwDmPreviewError nRetVal2 = 0;
            Image image = default(Image);

            //Access to interface
            swClassFact = new SwDMClassFactory();
            swDocMgr = (SwDMApplication)swClassFact.GetApplication("Post your code here");
            swDoc = (SwDMDocument)swDocMgr.GetDocument(sDocFileName, nDocType, false, out nRetVal);
            Debug.Assert(SwDmDocumentOpenError.swDmDocumentOpenErrorNone == nRetVal);
            swCfgMgr = swDoc.ConfigurationManager;

            pathLabel.Text = "Path to file: " + swDoc.FullName;
            configLabel.Text = "Active config: " + swCfgMgr.GetActiveConfigurationName();
            vCfgNameArr = (string[])swCfgMgr.GetConfigurationNames();

            foreach (string vCfgName in vCfgNameArr)
            {
                //get preview
                swCfg = (SwDMConfiguration7)swCfgMgr.GetConfigurationByName(vCfgName);
                pPreview = (IPictureDisp)swCfg.GetPreviewPNGBitmap(out nRetVal2);
                image = Support.IPictureDispToImage(pPreview);
                //insert to picturebox
                pictureBox1.BackgroundImage = image;
            }
            swDoc.CloseDoc();
        }

回答2:

You can use unmanaged windows shell methods to get the thumbnail

Here is the code (not a small one)

But results are far from perfect.

• debugging is very hard, unspecified error are common
• there has to be specific file reader availible on target machine (e.g. pdf-reader for pdfs, didn't tried it on SolidWorks)
• can work only in Windows
• performance issue
• thumbnails low quality (tried it with pdf)