jQuery & jQueryUI Base

HTML

<link rel="stylesheet" href="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.13/themes/black-tie/jquery-ui.css">
<script src="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.13/jquery-ui.js"></script>
<input id="myInput"/>

JavaScript

$("#myInput").autocomplete({
    source: ["Test", "This", "Doesnt", "Close"],
    minLength: 0,
    select: function (event, ui) {
        // Add custom login to manipulate ui.item.label (and ui.item.value if required.)
        // We've customised how we want the select to "work" so prevent the default
        // of auto clearing the input.    
        event.preventDefault();    
    },
    close : function(event)
    {
        // we're closing the autocomplete - check if the input still has focus...
        if ( ($("#myInput").is(":focus")) )
        {
            // prevent the auto complete from closing.
            event.preventDefault();
            
           // Make sure we're reshowing the autcomplete - since the input would have momentarily
            // lost focus when we selected an item.
            $("#myInput").autocomplete("search", "")
        }        
    }
});

$("#myInput").focus(function () {
    // We're not taking any filtering into account for this example.
    $(this).autocomplete("search", "")
});