The following table shows the combination-box styles:
┌────────────────────┬────────────────────────────────────────┐ │Style Name │Description │ ├────────────────────┼────────────────────────────────────────┤ │CBS_SIMPLE │Creates a simple combination box that │ │ │always displays its list box. The user │ │ │can enter and edit text in the entry │ │ │field or choose items from the list box.│ ├────────────────────┼────────────────────────────────────────┤ │CBS_DROPDOWN │Creates a drop-down combination box that│ │ │displays its list box only if the user │ │ │clicks the drop-down icon at the right │ │ │end of the entry field. The │ │ │combination-box control hides the list │ │ │box when the user clicks the icon a │ │ │second time. In a drop-down combination │ │ │box, the user can enter and edit text in│ │ │the entry field or choose items from the│ │ │list box. │ ├────────────────────┼────────────────────────────────────────┤ │CBS_DROPDOWNLIST │Creates a drop-down-list combination box│ │ │that is similar to the drop-down │ │ │combination box, except that the user │ │ │can choose items only from the list box.│ │ │The user cannot enter or edit text in │ │ │the entry field. │ └────────────────────┴────────────────────────────────────────┘
For combination boxes that have the CBS_DROPDOWN or CBS_DROPDOWNLIST styles, an application can display the list by using the CBM_SHOWLIST message.
An application can determine whether the list is already showing by using the CBM_ISLISTSHOWING message.
Applications also can use any of the entry-field (EM_) and list-box (LM_) messages with combination boxes. Entry-field messages affect the entry field; list-box messages affect the list box. For example, an application can use the LM_INSERTITEM message to insert items into the list box.