Search Text in DWG File using C# .NET

readme.md

You can read more details at: Search Text in DWG Drawing File Programmatically in C#

search-text-in-dwg.cs

// Load an existing DWG file as CadImage.
using (CadImage cadImage = (CadImage)Aspose.CAD.Image.Load(sourceFilePath))
{
    // Search for text in the file 
    foreach (CadBaseEntity entity in cadImage.Entities)
    {
        // We iterate through CadText entities, but some other entities may contain text also, e.g. CadMText and others
        IterateCADNodes(entity);
    }

    // Search for text on specific layout get all layout names and link each layout with corresponding block with entities
    CadLayoutDictionary layouts = cadImage.Layouts;
    string[] layoutNames = new string[layouts.Count];
    int i = 0;
    foreach (CadLayout layout in layouts.Values)
    {
        layoutNames[i++] = layout.LayoutName;
        System.Console.WriteLine("Layout " + layout.LayoutName + " is found");

        // Find block, applicable for DWG only
        CadBlockTableObject blockTableObjectReference = null;
        foreach (CadBlockTableObject tableObject in cadImage.BlocksTables)
        {
            if (string.Equals(tableObject.HardPointerToLayout, layout.ObjectHandle))
            {
                blockTableObjectReference = tableObject;
                break;
            }
        }

        if (blockTableObjectReference != null)
        {
            // Collection cadBlockEntity.Entities contains information about all entities on specific layout
            CadBlockEntity cadBlockEntity = cadImage.BlockEntities[blockTableObjectReference.BlockName];
        }
    }

    // Export to PDF
    CadRasterizationOptions rasterizationOptions = new CadRasterizationOptions();
    rasterizationOptions.PageWidth = 1600;
    rasterizationOptions.PageHeight = 1600;
    rasterizationOptions.AutomaticLayoutsScaling = true;

    // If cadBlockEntity collection for selected layout or entitiesOnLayouts collection by layout's BlockTableRecordHandle (for dxf) is empty
    rasterizationOptions.Layouts = new[] { "Layout1" };

    ImageOptions.PdfOptions pdfOptions = new PdfOptions();

    pdfOptions.VectorRasterizationOptions = rasterizationOptions;
    cadImage.Save("SearchText_CAD.pdf", pdfOptions);
}





public static void SearchTextInDWGAutoCADFile()
{
    // The path to the documents directory.            
    string sourceFilePath = "search.dwg";
    // Load an existing DWG file as CadImage. 
    CadImage cadImage = (CadImage)Aspose.CAD.Image.Load(sourceFilePath);

    // Search for text in the entities section 
    foreach (var entity in cadImage.Entities)
    {
        IterateCADNodes(entity);
    }

    // Search for text in the block section 
    foreach (CadBlockEntity blockEntity in cadImage.BlockEntities.Values)
    {
        foreach (var entity in blockEntity.Entities)
        {
            IterateCADNodes(entity);
        }
    }
}



private static void IterateCADNodes(CadBaseEntity obj)
{
    switch (obj.TypeName)
    {
        case CadEntityTypeName.TEXT:
            CadText childObjectText = (CadText)obj;

            Console.WriteLine(childObjectText.DefaultValue);

            break;

        case CadEntityTypeName.MTEXT:
            CadMText childObjectMText = (CadMText)obj;

            Console.WriteLine(childObjectMText.Text);

            break;

        case CadEntityTypeName.INSERT:
            CadInsertObject childInsertObject = (CadInsertObject)obj;

            foreach (var tempobj in childInsertObject.ChildObjects)
            {
                IterateCADNodes(tempobj);
            }
            break;

        case CadEntityTypeName.ATTDEF:
            CadAttDef attDef = (CadAttDef)obj;

            Console.WriteLine(attDef.DefaultString);
            break;

        case CadEntityTypeName.ATTRIB:
            CadAttrib attAttrib = (CadAttrib)obj;

            Console.WriteLine(attAttrib.DefaultText);
            break;
    }
}