Tutorial: Getting Started with the AutoLISP Extension (AutoLISP/VS Code)

Prerequisites

1. Install Visual Studio Code on your workstation.
2. Install and configure the AutoCAD AutoLISP Extension.

Topics in this Tutorial

• Create an AutoLISP (LSP) File
• Load an AutoLISP (LSP) File

Launch Visual Studio (VS) Code

The following methods can be used to launch Visual Studio Code after it has been installed:

Windows

• In File Explorer, click Start menu > Visual Studio Code > Visual Studio Code.
• In AutoCAD, not AutoCAD LT, at the Command prompt, enter vlisp. If displayed, read and close the informational message to proceed.
  Note: Visual Studio Code might prompt for permission to allow the AutoCAD AutoLISP Extension to open a URI that displays a message box. Click Open to allow the extension to display the informational message during startup, or click Cancel to suppress the display of the informational message. Check "Don't ask again for this extension." to have VS Code remember your choice.

Mac OS

• In Finder, click Go > Applications and then click Visual Studio Code in the Applications window.

Create an AutoLISP (LSP) File

LSP files are used to store AutoLISP code statements that can later be executed in a drawing and shared with others.

The following steps explain how to create an AutoLISP (LSP) file named Create-LSP-Tutorial.lsp in the open working folder.

1. In Visual Studio Code, on the Activity Bar, click Explorer.
2. In the Explorer view, adjacent to the open folder's name, click New File.
   
3. In the in-place editor, type Create-LSP-Tutorial.lsp and press Enter.

   If you enter a different name, make sure to include the .lsp file extension.

4. In the Create-LSP-Tutorial.lsp editor window, copy/paste or type the following:

   ;; Displays a message box containing the entered text
   (defun c:hello ( / msg)
   (setq msg (getstring T "\nEnter a message: "))
   (alert msg)
   )
   
   ;; Draws a line between two points
   (defun c:drawline ( / pt1 pt2) ;; Declared local variables
   ;; Prompt for two points
   (setq pt1 (getpoint "\nSpecify start point of line: ")
   pt2 (getpoint pt1 "\nSpecify end point of line: ")
   )
   
   ;; Check to see if the user specified two points
   (if (and pt1 pt2)
   (command "_.line" pt1 pt2 "")
   (prompt "\nInvalid or missing point(s)")
   )
   
   ;; Exit quietly
   (princ)
   )
   
   (prompt "\nAutoLISP Tutorial file loaded.")
   (princ) ; Suppress the return value of the prompt function

5. One the menu bar, click File menu > Save to save the changes to the LSP file.
6. Click File menu > Close Editor or Close (X) on the file's tab to close the editor window.

Load an AutoLISP (LSP) File

AutoLISP code statements stored in LSP files must be loaded into a drawing open in AutoCAD before they can be executed. While Visual Studio Code can be used to create and load LSP files, you will typically want to load your custom programs directly into AutoCAD before using them.

The following steps explain how to load the Create-LSP-Tutorial.lsp file into AutoCAD.

1. In AutoCAD, do one of the following:
   • (Windows) On the ribbon, click Manage tab > Applications panel > Load Application.
   • (Mac OS) On the Mac OS menu bar, click Tools > Load Application.
   • At the Command prompt, enter appload.
2. In the Load/Unload Applications dialog box, browse to the LSP Files folder or the folder in which you stored the Create-LSP-Tutorial.lsp file.
3. Select the Create-LSP-Tutorial.lsp file and click Load.
4. If the File Loading – Security Concern dialog box is displayed, click Load again.
5. Click Close to return to the application window.
6. You should see the following message in the Command History window.

   AutoLISP Tutorial file loaded.

7. At the Command prompt, enter hello.
8. At the Enter a message: prompt, type a text string and press Enter.

   A message box with the entered text string is displayed.

9. Click OK to close the message box.