Add import primitives to cross-section

StructureHelperCommon/Services/Exports/EntitiesImportFromDxfLogic.cs

@@ -0,0 +1,39 @@
+using netDxf;
+using netDxf.Entities;
+using netDxf.Header;
+using StructureHelperCommon.Services.Exports.Factories;
+using System.Collections.Generic;
+using System.IO;
+
+namespace StructureHelperCommon.Services.Exports
+{
+    public class EntitiesImportFromDxfLogic : IImportFromFileLogic
+    {
+        public string FileName { get; set; }
+        public List<EntityObject> Entities { get; set; } = [];
+        public void Import()
+        {
+            string extension = Path.GetExtension(FileName).ToLowerInvariant();
+            if (extension == ".dxf")
+            {
+                GetEntities();
+            }
+
+        }
+
+        private void GetEntities()
+        {
+            // this check is optional but recommended before loading a DXF file
+            DxfVersion dxfVersion = DxfDocument.CheckDxfFileVersion(FileName);
+            // netDxf is only compatible with AutoCad2000 and higher DXF versions
+            if (dxfVersion < DxfVersion.AutoCad2000) return;
+            // load file
+            DxfDocument dxf = DxfDocument.Load(FileName);
+            Entities.Clear();
+            if (dxf != null)
+            {
+                Entities.AddRange(dxf.Entities.All);
+            }
+        }
+    }
+}