Function Syntax: ExpFltr / ImpFltr / ExpFltrDebug Version: 1.1 Date: 20.06.2026 6:38:53PM https://forums.autodesk.com/t5/visual-lisp-autolisp-and-general/lisp-to-export-import-the-layers-properties-filter-in-autocad/td-p/10379159 Description This program allows the user to export a named layer property filter from the current drawing to an external file. The output is saved as a .lft file. Purpose The function simplifies the transfer of layer filters between drawings by allowing you to export them individually. Main Functionalities • Accesses the drawing's Extension Dictionary to locate layer filter data. • Retrieves all available layer property filters. • Displays a list of filters using a ListBox for user selection. • Prompts the user to choose a location and name for the export file. • Saves the selected filter's data in a structured format to a .lft file. • Adds a note at the top of the file: //Layer filter export, DO NOT MODIFY. User Prompts • Prompts the user with: "Choose the filter to export". • Then opens a file dialog to save the export file. Error Handling If no property layer filters exist in the drawing, the program displays: "None property layer filter in this drawing" Notes • Uses the ObjectARX COM API via vlax and vla functions. • The exported file can later be imported into other drawings using the complementary IMPFLTR function (not shown here). Description 📤 Export_Layer_Filter is an AutoCAD AutoLISP tool for exporting layer property filters to reusable .lft files. 🗂️ It adds a DCL interface for multi-filter selection, xref prefix handling, predefined project folders, and folder management. Function Syntax 🚀 Export command: ExpFltr 📥 Import command included: ImpFltr 🧪 Debug command: ExpFltrDebug 🗂️ The DCL workflow supports Select All, Select None, Use Xref, Prefix, Suffix, predefined folders, and Manage Folders. SEO Optimized Overview 📤 Export_Layer_Filter is an SEO-friendly AutoCAD layer filter export utility for transferring property layer filters between drawings and projects. 🧱 Based on the gile layer filter export and import concept, this enhanced version writes selected AutoCAD layer filters to an .lft file using a v2 multi-filter format with a //COUNT header. 🔤 Prefix and suffix controls can modify NAME== patterns in the exported filter expressions, making the workflow practical for xref-layer naming standards such as DrawingName|LayerName. 🗂️ Predefined folder shortcuts help store layer-filter exports in project Layer_Status directories instead of manually browsing every time. 📌 This is useful for Civil 3D project templates, xref layer visibility standards, layer-state administration, CAD QA checks, and drawing setup automation. Primary Workflow 1️⃣ Load the AutoLISP file in AutoCAD or Civil 3D with APPLOAD or your menu loader. 2️⃣ Run the command shown above from the AutoCAD command line. 3️⃣ Follow the dialog, selection prompts, or file prompts used by Export_Layer_Filter. 4️⃣ Review the command-line report and drawing result before continuing production work. Functionalities ✅ Export one or many AutoCAD property layer filters to a single .lft file. ✅ Use a DCL list with multi-select, Select All, and Select None. ✅ Apply xref-aware prefixes and suffixes to NAME== layer patterns during export. ✅ Use predefined folders for fast project-specific save locations. ✅ Manage folder presets directly from the dialog. ✅ Import v1 and v2 .lft files or layer filters from DWG and DWT sources. ✅ Include a debug command to verify DCL creation and dialog loading. Important Functions and AutoCAD API 🧩 EF_str->lst and EF_JoinStr handle list string parsing for multi-selection and export data preparation. 🧩 EF_ApplyPrefix and EF_ApplyPrefixSuffix modify NAME== rules before writing the .lft export. 🧩 EF_LoadPFOpts and EF_SavePFOpts persist predefined folder options. 🧩 EF_ManageFolders opens a dedicated DCL manager for adding, updating, removing, and saving folder shortcuts. 🧩 getFilterDatas reads ACAD_LAYERFILTERS and ACLYDICTIONARY xrecord data from the active drawing. 🧩 addLayerFilter can rebuild exported layer-filter data in a target drawing. Result 🎯 The result is a portable .lft layer-filter export file that can be reused in other drawings. 🟢 Multiple filters can be exported together, reducing repetitive AutoCAD Layer Properties Manager setup work. Operational Notes and Limitations ⚠️ The exported .lft file contains AutoCAD layer filter xrecord data and should not be manually edited unless you know the structure. 🧠 Prefix and suffix logic is intended for layer-name pattern rules; verify results when applying it to complex filters. 📌 The routine works with AutoCAD layer property filters stored in the drawing extension dictionaries. Tags 🏷️ AutoCAD, 🏷️ AutoLISP, 🏷️ Civil 3D, 🏷️ Layer Filters, 🏷️ Layer Management, 🏷️ Xref Layers, 🏷️ DCL Dialog, 🏷️ LFT Export, 🏷️ CAD Standards