You can kick off special processes from your symbol when a user performs an particular action, such as double-clicking the symbol, dragging it, or even modifying the symbol. The special process can be a .DLL, .OCX, or .EXE file that you created in other programming software. You can select an action from the Standard Actions tab on the Symbol Properties dialog box.
You can also specify special processes that you can execute when you select a symbol, click the right mouse button, and then click a custom command on the shortcut menu. The command names of the processes that you define appear at the top of the shortcut menu. You define these processes on the Custom Actions tab of the Symbol Properties dialog box.
To use this functionality, you must install the Symbol Authoring option.