To enable VBA for AutoCAD 2015 64-bit, you must download and install the specific :
method is the primary way to generate text programmatically. autocad 2015 vba module 64-bit
This works identically in 32-bit and 64-bit AutoCAD 2015 because it uses AutoCAD’s object model, not Windows API. To enable VBA for AutoCAD 2015 64-bit, you