Dialog boxes provide users of AutoCAD and IntelliCAD the ability to create professional-looking applications with minimal effort. Many existing LISP applications can be redesigned โปรแกรมมวย around this GUI making programs more efficient. This allows the user to operate the application with very little understanding. The user selects operations from the dialog and much of the work is done automatically.
You do not need to be an experienced programmer to master the LISP language as LISP is among the easiest programming languages to learn. Designing and implementing DCL programs involves two steps: The DCL or Visual Dialog programming step and the LISP code-programming step.
What is DCL?
DCL is an acronym for Dialog Control Language, a separate programming language that you can use with a CAD program to create custom dialog boxes. DCL code defines the appearance and content of the dialog box. An LISP application is required to control the use and behavior of the dialog box.
In this step, you use a text editor, such as Notepad or an API such as the VLISP editor built into AutoCAD, to create an ASCII text file, which contains the DCL tile definitions, saved with the.DCL extension. The arrangement of elements (tiles) in a dialog box consists of buttons, edit boxes, text tiles, and list tiles, is determined by their order in the DCL file. Each elements size and functionality is controlled by the tile’s attributes. The parts of a dialog box define its behavior and depend on the LISP application that controls it.
What is LISP?
The LISP found in AutoCAD and IntelliCAD, is a version of the programming language known as LISP, an acronym for LISt Processing, also known as Lost In Stupid Parenthesis. AutoCAD and IntelliCAD based programs include an implementation of the LISP language, with nearly all the functions available in AutoCAD’s AutoLISP, to program and control dialog boxes, known as the Programmable Dialogue Box (PDB) facility.
In this step, you also use a text editor or an API (Application Programming Interface) to create an ASCII text file, containing the LISP code, saved with the.LSP extension. The LISP file is a separate file from the DCL file and must be loaded into the CAD program for the program to execute. When the program is executed, displaying the dialog box inside AutoCAD or IntelliCAD involves a few steps. The LISP program must load the DCL file into memory then activated it before the dialog appears on the CAD screen for interaction with the user.
To get started or learn more about DCL Programming with LISP, visit The AutoLISP Toolbox and refer to the DCL Programming section.
Barry began using AutoCAD software with Release 1.2 more than 20 years ago. He started writing an AutoLISP Tutorial for CADalyst magazine in 1988 and continued writing different AutoLISP programming articles for the next 15 years.