javascript - Passing the values of server controls to ASPx client side events -

i have combobox in page:

<dx:aspxcombobox id="combositeid" runat="server" style="margin-bottom: 0px" valuefield="name" width="120px"></dx:aspxcombobox>

when user select item combobox, want query mssql , show returning value on label:

<dx:aspxlabel id="aspxlabel1" runat="server" text="value here"></dx:aspxlabel>

it seems client side event appropriate 1 put code

<clientsideevents textchanged="function(s, e) {     // do? }" />

what best way succeed task?

if client-side, need call web service, have web service query database, , return results via json. looking do? if are, webservice trick.

or, can set autopostback="true", page posts server, , there query db , load results in label.

Brande