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RadComboBox supports a number of client-side events that let you customize its behavior:

To use these events, simply write a JavaScript function that can be called when the event occurs. Then assign the name of the JavaScript function as the value of the the corresponding RadComboBox property.

<script language="javascript" type="text/javascript">
    function MyClientBlur(sender, eventArgs) {


You can also assign event handlers in client-side code:

function MyClientBlur(sender, eventArgs) {

function pageLoad() {
    var combo = $find("<%= RadComboBox1.ClientID %>");

Another advantage of the client-side API is that you can detach an event handler dynamically:

function RemoveEventHandler() {
    var combo = $find("<%= RadComboBox1.ClientID %>");

Note that on the client-side, the names of events are slightly different than on the server side. The following table shows the correspondance between client-side and server-side names:

Client-SideName Server-Side Name Methods to Add and Remove
OnClientLoad load add_load, remove_load.
OnClientKeyPressing keyPressing add_keyPressing, remove_keyPressing.
OnClientSelectedIndexChanging selectedIndexChanging add_selectedIndexChanging, remove_selectedIndexChanging.
OnClientSelectedIndexChanged selectedIndexChanged add_selectedIndexChanged, remove_selectedIndexChanged.
OnClientItemsRequesting itemsRequesting add_itemsRequesting, remove_itemsRequesting.
OnClientItemsRequested itemsRequested add_itemsRequested, remove_itemsRequested.
OnClientDropDownOpening dropDownOpening add_dropDownOpening, remove_dropDownOpening.
OnClientDropDownOpened dropDownOpened add_dropDownOpened, remove_dropDownOpened.
OnClientDropDownClosing dropDownClosing add_dropDownClosing, remove_dropDownClosing.
OnClientDropDownClosed dropDownClosed add_dropDownClosed, remove_dropDownClosed.
OnClientItemsRequestFailed itemsRequestFailed add_itemsRequestFailed, remove_itemsRequestFailed.
OnClientFocus onClientFocus add_onClientFocus, remove_onClientFocus.
OnClientBlur onClientBlur add_onClientBlur, remove_onClientBlur.
OnClientTextChange textChange add_textChange, remove_textChange.
OnClientItemDataBound itemDataBound add_itemDataBound, remove_itemDataBound.

See Also

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