Studio for iPhone includes a rich client-side object model in which includes several client-side events. You can access these client-side events from the Properties window. To create a new client-side event, select the drop-down arrow next to a client-side event and select Add new client side handler.
Once you've added the client-side handler, Visual Studio will add a script to the Source view. That script will resemble the following:
<script id="ComponentOneClientScript" type="text/javascript">
function C1PickerView1_OnClientSelectedIndexChanged(){
//
// Put your code here.
//
};
</script>
For information about these client-side events, see the client-side reference section.