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Working at Client-side
RadListBox provides a client-side API for adding, deleting and updating items.
Adding Items
To add an item, use the RadListBoxItemCollection.add method. If you want the change to the listbox items to persist after a postback, you must wrap the call to the add method between a call to the radListBox.trackChanges() method and a call to the radListBox.commitChanges() method:
JavaScript
<input type="button" value="Add" onclick="AddNewItem()" />
<script type="text/javascript">
function AddNewItem() {
var lb = $find("<%= RadListBox1.ClientID %>");
var item = new Telerik.Web.UI.RadListBoxItem();
item.set_text("New Item");
lb.trackChanges();
lb.get_items().add(item);
item.select();
lb.commitChanges();
}
</script> Removing items
Use the remove method of the RadListBoxItemCollection object to remove items:
JavaScript
<input type="button" value="Remove" onclick="RemoveItem()" />
<script type="text/javascript">
function RemoveItem() {
var lb = $find("<%= RadListBox1.ClientID %>");
var item = lb.get_selectedItem();
lb.trackChanges();
lb.get_items().remove(item);
lb.commitChanges();
}
</script> Enabling and Disabling items
Use the disable() and enable() methods of the RadListBoxItem object to disable or enable items:
JavaScript
<input type="button" value="Disable on the client" onclick="DisableItem()" />
<script type="text/javascript">
function DisableItem() {
var lb = $find("<%= RadListBox1.ClientID %>");
var item = lb.get_selectedItem();
lb.trackChanges();
item.disable();
lb.commitChanges();
}
</script> Checking and Unchecking items
Use the check() and uncheck() methods of the RadListBoxItem object:
JavaScript
<input type="button" value="Check on the client" onclick="CheckItem()" />
<script type="text/javascript">
function CheckItem() {
var lb = $find("<%= RadListBox1.ClientID %>");
var item = lb.get_selectedItem();
item.check();
}
</script>