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use DLLs to create new commands that operate exactly the same way as native
AutoCAD commands.
You can use ObjectARX libraries in conjunction with other AutoCAD
programming interfaces, such as AutoLISP or VBA, enabling cross-API
integration.
The ObjectARX programming environment is described in the ObjectARX
Developer's Guide. The documentation is part of the ObjectARX Software
Development Kit, which can be downloaded from the Development Tools
section of the Autodesk website. For more information, on the InfoCenter
toolbar, to the right of the Help button, click the drop-down arrow. From the
menu, click Additional Resources ➤ Developer Help. Click ObjectARX once
the Help systems opens.
Use ObjectARX Applications
To load an ObjectARX application, you use the Load option of the ARX
command. After loading, all commands defined by this application are
available at the command prompt.
Some ObjectARX applications use large amounts of system memory. If you
are finished using an application and want to remove it from memory, use
the Unload option of ARX.
You can also load an ObjectARX application with the arxload AutoLISP
function. The syntax for the arxload function is almost identical to that of
the load function used with AutoLISP files. If the arxload function loads the
ObjectARX program successfully, it returns the program name. The syntax for
the arxload function is as follows:
(arxload filename [onfailure])
The two arguments for the arxload function are filename and onfailure. As
with the load function, the filename argument is required and must be the
complete path name description of the ObjectARX program file to load. The
onfailure argument is optional and typically not used when you load
ObjectARX programs from the command prompt. The following example
loads the ObjectARX application myapp.arx.
(arxload "myapp")
As with AutoLISP files, AutoCAD searches the library path for the specified
file. If you need to load a file that is not in the library path, you must provide
the full path name description of the file.
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