jQuery UI autocomplete caching using $.map function

Question

I am trying to implement caching using jQuery UI autocomplete. I am using jQuery 1.4.4 and UI 1.8.6

Here is the basic code that I got working:

$('#searchbox').autocomplete({
    source: function(request, response) {
            if (xhr === lastXhr) {
                response( $.map(data, function(item) {
                    return {
                        label: item.NAME + (item.PRFNM ? ' (' + item.PRFNM + ')' : '') + ', ' + item.JOBTITLE,
                        value: item.NAME
                    };
                }));
            } 
        });
    }
});

Here is my attempt to get caching to work from looking at the example:

var cache = {},
    lastXhr;
$('#searchbox').autocomplete({
    source: function(request, response) {
        var term = request.term;
        if (term in cache) {
            response($.map(cache[term], function(item) {
                return {
                    label: item.NAME + (item.PRFNM ? ' (' + item.PRFNM + ')' : '') + ', ' + item.JOBTITLE,
                    value: item.NAME
                };
            }));
        }
        lastXhr = $.getJSON( "getdata.php", request, function(data, status, xhr) {
            cache[term] = $.map(data, function(item) {
                return {
                    label: item.NAME + (item.PRFNM ? ' (' + item.PRFNM + ')' : '') + ', ' + item.JOBTITLE,
                    value: item.NAME
                };
            }); 
            if (xhr === lastXhr) {
                response( $.map(data, function(item) {
                    return {
                        label: item.NAME + (item.PRFNM ? ' (' + item.PRFNM + ')' : '') + ', ' + item.JOBTITLE,
                        value: item.NAME
                    };
                }));
            } 
        });
    }
});

Any takers out there?

Answer 1

Here's my working example of jQuery UI's autocomplete using cache. Hope it helps:

    var cache = {};
    $("#textbox").autocomplete({
      source: function(request, response) {
       if (request.term in cache) {
        response($.map(cache[request.term].d, function(item) {
         return { value: item.value, id: item.id }
        }))
        return;
       }
       $.ajax({
        url: "/Services/AutoCompleteService.asmx/GetEmployees",  /* I use a web service */
        data: "{ 'term': '" + request.term + "' }",
        dataType: "json",
        type: "POST",
        contentType: "application/json; charset=utf-8",
        dataFilter: function(data) { return data; },
        success: function(data) {
         cache[request.term] = data;
         response($.map(data.d, function(item) {
          return {
           value: item.value,
           id: item.id
          }
         }))
        },
        error: HandleAjaxError  // custom method
       });
      },
      minLength: 3,
      select: function(event, ui) {
       if (ui.item) {
        formatAutoComplete(ui.item);   // custom method
       }
      }
     });

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