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Click any image to enlarge it, then use the left and right arrows on your keyboard to scroll through all the images on this page.

Recently my office has become an unpleasant place to be. Although I’ve still started work each day eager and energetic, my discipline has quickly sagged and by mid-morning I’ve been giving priority to any task that will take me away from my desk.

The reason? I wasn’t sure for a while, but the ultimate diagnosis was the ever-increasing noise made by my computer. Sure, it’s a powerhouse, but I’d selected it because it was supposed to be quiet. Initially it did seem silent compared to its predecessor but, once I had it fully set up and installed under my desk, it showed its true colours. Lately it’s started each morning with a purr and slowly worked its way into a roar.

I hasten to say that my computer is well maintained, its internals regularly dusted and vacuumed. The cooling fans are all in good working order, none of the bearings or sleeves is suspect and CPU temperatures are always at the lower end of the scale. The machine has no cause for such noisy complaint.

It’s a subtle poison, noise – especially when it grows incrementally. It’s taken me some months to realise why I’d started to dislike being at my desk. But yesterday afternoon I powered off during network testing and, as the fans turned off, the light turned on. It was the noise of the computer that was my problem.

Identifying the cause of the malaise wasn’t a cure though; I considered the options.

I could move the offender further from my desk by multiplying the existing metres of spaghetti in the unholy bolognaise that is my office. But that would only reduce the noise a little: it would still sit in the corner of the office like a rocket preparing for takeoff. There’s no way to actually get the box out of the room without major reconstruction.

I briefly considered putting the computer elsewhere on the network and running it as a remote desktop: this is the sort of fantasy you have when you’ve lived the whole day next to a jet engine. Then I realised I’d still need a reasonably powerful computer at my desk to connect with; that may also be noisy. I’d be trading one set of problems for another, with a side helping of inconvenience.

The most promising resolution seemed to be rebuilding the computer with low noise components. After a little research I decided that a reasonable first step would be to replace whichever component was the most obviously noisy. So this morning I opened the case while the machine was in full song. It was immediately obvious that the CPU fan was the primary culprit. But then a strange thing happened …

… I sat transfixed as the tortured beast slowly wound its way down from supersonic to subliminal. I’d never had the case open before while the computer was running: I’d always turned it off to clean it or maintain it. The puir wee darling was starving for fresh air.

The case has two side panel mesh vents in addition to standard venting on the rear. But it had no case fan to force air through the enclosure, and clearly the existing apertures were insufficient. As the temperature inside rose, the CPU fan set out to do battle, valiantly shifting as much air as it could in a vain attempt to bring the temperature down. Removing the side panel removed the problem.

I’ll install a case fan – that’s the prudent thing to do. But for the rest of the day I’m running with a naked computer, and loving the peace and quiet.

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JQuery is the most widely used javascript framework on the web. Its companion user interface library, jQueryUI, also has a lot to offer. In a recent release jQueryUI began offering a baked-in autocomplete function – not a third-party component, but part of the jQueryUI core itself. Using jQueryUI you can now add auto-complete functionality to a standard text input in just a couple of lines of client-side code.

Here’s the simplest possible example of jQueryUI’s autocomplete function. You specify the id of the text input to which you want to apply autocomplete, specify a source for the data and some code (not included) to invoke when the user selects one of the proffered options.

  $("#textinputid").autocomplete({

    source: "http://www.server.com/autocomplete.php",

    minLength: 2,

    select: function(event, ui){

      // Do something when an item in the autocomplete menu is selected

    }

  });

JQueryUI does the rest: it’s very simple.

There’s a problem though. The jQueryUI team provides three options for populating the autocomplete menu via the source attribute. The one I most commonly use is illustrated above: a string containing a URL. JQueryUI will append to this a parameter called atom that contains the value of the text input. This works fine … unless you also want to include data from, say, checkboxes on the page.

  $("#textinputid").autocomplete({

    source: "http://www.server.com/autocomplete.php?active=" + $('#checkboxid').prop(': checked'),

    minLength: 2,

    select: function(event, ui){

      // Do something when an item in the autocomplete menu is selected

    }

  });

The above code does work, but the checkbox value never changes: it’s evaluated when the autocomplete function is loaded. If it’s checked then, it’s always checked. If it’s not, it’s not. Nothing the user does will change it. While the code is simple and easy to follow, it’s not terribly useful.

JQueryUI does provide other ways of populating the source attribute, but they’re a little more complicated than a simple concatenated string: you have to do a bit more of the heavy lifting yourself. Thankfully there’s an easy workaround.

JQueryUI’s autocomplete provides an optional search attribute which is invoked just before autocomplete attempts to retrieve matches for the atom entered in the text input. Usefully, this isn’t evaluated when the autocomplete function is loaded, and it can be used to set the source parameter.

  $("#textinputid").autocomplete({

    source: "",

    minLength: 2,

    select: function(event, ui){

      // Do something when an item in the autocomplete menu is selected

    },

    search: function(event, ui){

      $("#textinputid").autocomplete({

        source: "http://www.server.com/autocomplete.php?active=" + 

          $('#checkboxid').prop(': checked')

      });    

    },

  });

While this approach is admittedly a little bit of a kludge, it’s not enough to offend my sensibilities. It works, it works robustly, and the code remains reasonably simple and easy to follow.

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