A combobox control is combination of textbox and listbox. This control enables user to select either by typing in the text into combobox or by selecting items from the list.
The combobox controls has three different style that can be set .
a) Drop down combo (style 0)
b) Simple combo (style 1)
c) Drop down list (style 2)
a)Drop down combo :
It first appears as only an editable area with down arrow button to drop down list portion with this style. We can either type text into text portion which is an editable area or select a value from drop down list. The list portion status hidden until the user clicks down arrow button to drop down list portion.
This style looks like listbox setting directory underneath a textbox. The listbox , which below textbox which is always visible showing an item present in it. Scrollbar
display decides the list if there are to many item to display in listbox area. So important thing is , list is always present below textbox. Hence there no downward arrow button which are used to open a list, in case of drop down combo.
c)Drop down list Combo:
The drop down list combobox terms combobox into drop down listbox at run time , the control looks like drop down combobox. The user click on down arrow view list. Main difference between drop down combo & drop down list combo are editable are in the drop down list disable i.e. means user can only select from item listed in portion of listbox of the combobox and he can?t type and item in the next or edit area of the combobox.