AutoCAD 2021: Defining and Attaching Block Attributes

by John Flanagan

What are Attributes?

An attribute is a label or tag that attaches data to a block. They can also be used to extract information into a database or table format.

You can associate more than one attribute with a block, provided that each attribute has a different tag. The AutoCAD software prompts you to provide values for each of the values that are associated with the block. The following illustration shows a "computer" block with four attributes to describe the computer’s capacity: CPU, Monitor, HDD, RAM and Station.

Defining Attributes

The Attribute Definition Dialogue Box is used to configure attributes before they are associated with a block.

In the Home tab>expanded block panel or Insert tab>Block Definition panel, click Define Attributes to create the attributes.

When you define an attribute, you specify:

• A unique tag that identifies the attribute by name (no spaces).
• A prompt that can be displayed as the block is inserted.
• A default value that is used if a variable value is not entered at the prompt.

Associating Attributes with Blocks

Once the attributes have been defined, they must be associated with a block. This is done by including attributes as part of the block while in the Block or Wblock command, or in the Block Editor authoring mode.

Select the attributes individually, rather than with a window or crossing box. The order in which the attribute information is displayed during block insertion depends on the order in which the attributes were selected for inclusion in the block.

Attribute information extracted from a drawing can be used in a spreadsheet or database to produce a parts list or a bill of materials. You can associate more than one attribute with a block, provided that each attribute has a different tag.