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Migrating from RadComboBox Classic to ASP.NET AJAX version

RadComboBox for ASP.NET AJAX has changed because of evolving to the ASP.NET Ajax framework and Telerik.Web.UI suite. All of the client-side properties and methods' names have changed along with several server API changes. Some properties and methods have been completely removed, while new ones have been added.The control's client-side API is not backward-compatible with RadComboBox Classic version. All the changes included in the AJAX RadComboBox's client-side API are listed below:

Client-side API Changes

RadComboBox class

The tlrkComboBoxes array has been removed. The Telerik.Web.UI.RadComboBox.ComboBoxes should be used instead. For more details please refer to the Client-Side Basics article.


RadComboBox Classic RadComboBox AJAX
HideDropDown hideDropDown
ToggleDropDown toggleDropDown
ShowDropDown showDropDown
Disable disable
Enable enable
FindItemByValue findItemByValue
FindItemByText findItemByText
GetText / SetText get_text / set_text
GetValue / SetValue get_value / set_value
RequestItems requestItems
ClearItems clearItems
ClearSelection clearSelection
ClientDataString The ClientDataString property has been removed. The OnClientItemsRequesting event's event arguments should be used instead:

function OnClientItemsRequesting(sender, eventArgs)
    //get the context object    
    var context = eventArgs.get_context();    
    //set a value to the context object    
    context["FilterString"] = eventArgs.get_text();  

Then, you can access the context object in the WebService method:

IDictionary<string, object> contextDictionary = (IDictionary<string, object>) context;
string txt = contextDictionary["FilterString"].ToStrring();

You can also access the context object in the ItemsRequested event handler using the event arguments:

protected void RadComboBox1_ItemsRequested(object sender, RadComboBoxItemsRequestedEventArgs e)
    string txt = e.Context["FilterString"].ToString();

RadComboBox Classic RadComboBox AJAX
MoreResultsBoxID get_moreResultsBoxElement()- returns the DOM element of the MoreResultsBox.
MoreResultsMessageBoxID get_moreResultsBoxMessageElement() - returns the DOM element of the MoreResultsBox element.
DropDownVisible get_DropDownVisible()
ImageID get_imageDomElement() - returns the DOM element of the drop arrow image.
InputID get_inputDomElement() - returns the DOM element of the input field.
DropDownID get_dropDownElement()- returns the DOM element of the drop-down area.
Items get_items() - returns an Items collection.
Enabled get_enabled() - returns true if the combobox is enabled, false otherwise. set_enabled(true) - enables the RadComboBox, set_enabled(false) - disables the RadComboBox.
SelectedItem get_selectedItem() / set_selectedItem(item)
HighlightedItem get_highlightedItem() / set_highlightedItem(item)

RadComboBoxItem class


RadComboBoxItem Classic RadComboBoxItem AJAX
Highlight highlight
UnHighlight unHighlight
Disable disable
Enable enable
Select select
SetAttribute setAttribute
Enabled get_enabled() - returns true if the item is enabled, false otherwise. set_enabled(true) - enables an item, set_enabled(false) - disables an item.
Index get_index()
ComboBox get_combobox()
Text get_text() / set_text(string)
Value get_value() / set_value(string)

RadComboBoxItemCollection class (new)

Member Notes
add Adds an item
insert Inserts an item
remove Removes an item
clear Clears the items
getItem Gets an item from the Items collection.
indexOf Returns the index of an item.
removeAt Removes an item at a specified index.
get_count Returns the count of the items.
trackChanges Indicates the beginning of client-side changes that are meant to be persisted on the server.
commitChanges Indicates the end of client-side changes that are meant to be persisted on the server.

Server-side API changes

RadComboBox class


RadComboBox Classic Notes
ContentFile Removed: The LoadContentFile method should be used instead.
ExternalCallbackPage Removed: An external streamer page is no longer needed. The items' population of the RadComboBox should be done via WebService instead.
IsCallBack Removed: The Page.IsCallBack property should be used instead.
Value Removed: With the new RadComboBox for ASP.NET AJAX , the SelectedValue property is persisted on the server even when the items are loaded on demand. Therefore, the Value property is no longer needed.
RadComboBoxItemsRequestedEventArgs.ClientDataString Removed: The RadComboBoxItemsRequestedEventArgs.Context property should be used instead. It returns an object of type IDictionary .
AfterClientCallBackError Changed to OnClientItemsRequestFailed.
GetXmlString Changed to GetXml (inherited from ControlItemContainer class).
LoadXmlString Changed to LoadXml (inherited from ControlItemContainer class).
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