How to display the pulldown button only

I am creating a customize combobox and 开发者_如何学运维want to use the default pulldown button used on <select> element. The combobox is composed of a textbox, a pulldown button and somewhat a table element containing the list. Everything is working except for displaying dropdown button. Note that I want to refrain from using any background image for the button. I want to use the default dropdown button. How can I make use of the dropdown button?

Maybe you could make a <select> element, then, using positioning in your stylesheet, cover it with the text field. If you position the textfield right, you should show only the pulldown button from your <select>.