Updating block in autocad
If the expression is a full Auto LISP function, it must return a string value (not an integer, real, list, or nil value).
The program must be encoded into the project description data as "(load 'filename.lsp')." It must be self-starting upon load.
For example, in a block containing an attribute whose tag is Cost and value is 19.99, the 19.99 value is unaffected if you change the tag from Cost to Unit Cost.
If the attribute carries a prompt value, this value is used as a prefix.For example, you may have used the Block Attribute Manager to modify attribute properties in several block definitions in your drawing but elected not to automatically update existing block references when you made the changes.Now that you are satisfied with the attribute changes you made, you can apply those changes to all blocks in the current drawing.The program is designed to run automatically when loaded and, after being correctly configured, may be added to the Startup Suite or to enable drawing titleblocks or other attributed blocks to be automatically updated upon opening a drawing or running a script.If loaded on startup, when a drawing is opened, a CSV file may be selected or automatically read by the program from a known location, and block attributes are automatically & silently updated using values corresponding to the rows associated with the active drawing in the CSV file.
"Now that the inserted working drawing is updated, WBlock it out to its original name, overwriting it.