Use the Behaviors panel to manage behaviors (and some Spry components) in Dreamweaver.
Window > Behaviors
Behaviors always attach to a tag. Be sure you have the correct tag selected before adding a behavior.
Adding behaviors — click the Plus button (+) to display a menu of Actions.
Screenshot of Behaviors panel: add behavior to <a> tag.
A grayed-out menu item indicates an Action which cannot be added to the currently selected tag; not all tags support all actions.
Here is the Behaviors panel with two Actions:
The first action is the standard Open Browser Window.
The second action — return false — was entered manually, by selecting an event and then typing directly into the Action field. This allows us to enter JavaScript code directly. This code will run when the event occures. In this example, “return false” makes the <a> tag ignore the click.