# BACTION Command [GstarCAD 2027](Help%20System/GSTARCAD/2027/Index.md) → [Commands](Help%20System/GSTARCAD/2027/Commands/(Commands).md) → [B](Help%20System/GSTARCAD/2027/Commands/B/(B).md) ## Function Description: This command is used to add actions to dynamic block definitions. This command is available only in the Block Editor. Actions define how the geometry of a dynamic block reference moves or changes when the custom properties of a block reference are manipulated in a drawing. You associate actions with parameters. ## Command Access: > **Icon:**  > **Menu:** / > **Ribbon:** Block Editor > Action > Action > **Toolbar:** / > **Command:** BACTION > **Alias: /** ## Command Prompts: ``` Select parameter: ``` --- **Related References：** - [Commands about Dynamic Blocks (GstarCAD 2026)](../../../2026/Commands/00%20Command%20Groups/Commands%20about%20Dynamic%20Blocks.md) **Related Tasks：** - [To Specify Settings for Parameters and Actions (GstarCAD 2026)](../../../2026/Commands/01%20Procedures/To%20Specify%20Settings%20for%20Parameters%20and%20Actions.md) - [To Specify the Text Color for Actions (GstarCAD 2026)](../../../2026/Commands/01%20Procedures/To%20Specify%20the%20Text%20Color%20for%20Actions.md) --- [Original help](https://www.gstarcad.net/help/GstarCAD_2027_en-US/detail/commandReferences_B/BACTION.html) · © Gstarsoft Co., Ltd.