Javascript Code
Please Note – this doesnt work with old version of js File

$('document').ready(function(){
$('#cboCity').live("change", function(){
alert('Hi there');
});

$('#btnChange').on("click", function(){
changeCities();
});
});

function changeCities()
{
strSelect = "<select id='cboCity' name='cboCity'><option>Chennai</option><option>Mumbai</option></select>";
$('#City').html(strSelect);
}

HTML Code

<input id="btnChange" type="button" name="btnChange" value="Change Me" /></pre>
<table>
<tbody>
<tr>
<td>
<div id="City">
<select id="cboCity" name="cboCity"><option>Chennai</option><option>Mumbai</option><option>Delhi</option><option>Kolkatta</option><option>Andrapradesh</option>
</select>

</div>
</td>
</tr>
</tbody>
</table>