Virtual block attributes

The A>V>C> Properties Palette will show "virtual" attributes in block properties, even if the block doesn't have them. Creating virtual attributes makes sense if most of your blocks need to have the same attribute. For example, all products need an "Article" and "Price." A virtual attribute will save time. You won't need to create an attribute for each block separately. And after extracting data into a table, you'll never see N/A—the Data Table program will assume all blocks have the attribute (even if they don't!) and will supply the desired default value. In most cases, constant attributes are more suitable for storing product information, since identical chairs have the same article and identical lamps have the same price. However, if you need to assign individual numbers to the same lamps in the layout, create a variable (not constant) virtual attribute called "Number."

Virtual Block Attributes

This field is responsible for variable attributes. They are visible in the properties panel and in the A>V>C> Properties Palette on the Block References tab. List one attribute per line, without commas. You can also include the attribute's default value. Write it after the equals sign (=). Do not include spaces. Virtual attributes are not displayed for annotative blocks. Virtual attributes can be extracted to tables and callouts for all blocks. If the attribute doesn't actually exist, the default value or an empty string (but not "n/a") will be substituted.

Virtual constant block attributes 

are also virtual attributes, but they are stored in the Block Definition, not the Block Reference. They are not visible in the properties panel, and in the A>V>C> Properties Palette, you must switch to the Block Definitions tab. Constant attributes store only one value, and you cannot enter different values ​​for different references to the same block. This field is used to enter attributes for Assemblies and other blocks, but not for Products.

Virtual block-product attributes 

are the same as constant attributes, but only for blocks marked as Products. By default, attributes with the same names as material properties are already entered here: Kind, Article, and so on. This allows you to extract product data for the Material Table using the same substitutions as material property substitutions, and thus create a procurement/delivery table.