You need to add a results handler:

$("#txtCity").autocomplete("<Your existing stuff here>").results(
         function(event, item, formatted)
         {
            // Use the item property
         }
      );

You need to add a results handler:

$("#txtCity").autocomplete("<Your existing stuff here>").result(
         function(event, item, formatted)
         {
            // Use the item property
         }
      );

You need to add a results handler:

$("#txtCity").results(
         function(event, item, formatted)
         {
            // Use the item property
         }
      );

You need to add a results handler:

$("#txtCity").autocomplete("<Your existing stuff here>").results(
         function(event, item, formatted)
         {
            // Use the item property
         }
      );