You can use the following built-in functions with combination box objects.
| Function | Description | 
| bottom [of] | Returns the line number of the last line in the combination box. | 
| top [of] | Returns the line number of the first line in the combination box (which is always 1). | 
| textual line from | Returns the text that appears on the specified line of the combination box. (See textual Object Inquiry Built-in Function in the Reference Guide.) | 
| selected line | Returns the currently selected line in a for each selected line loop. | 
| selected line from | Returns the line number of the line that the user has selected from the combination box. | 
| window | Returns the line number of the first line | 
| yposition of | displayed in the combination box. |