Get value DHTMLX Combo

Hello, I’m a newbie of AJAX programming, I have a problem to get value of selected combo in order to complete my SQL Query. I cannot access the value using php. Please help me.

If you are using default ( non AJAX ) way of form sending - the combo will be sent as part of normal FORM submit ( the name of input will be equal to name of source select box in case of generation from select, or may be set by second parameter of constructor in case of custom initialization )

If you are using some custom way of data sending, the value of combo can be reached as
    var combo = new dhtmlXCombo(…
    var value = combo.getActualValue();