JSIO URLs

Posted on by

The clever bit about JSIO is the placeholder URLs – i.e. the “jsio.gif#…” that goes in your image src attributes and background-image CSS properties. Everything after the “#” is the filename of the image that should be displayed. It doesn’t have to be the filename at all, it could just be a single letter or number or symbol or whatever. It doesn’t matter to JSIO. To JSIO, everything after the “#” is just a key into the resources object that holds data uri encoded images. As long as the key is unique (which it will be if you use filenames, since no two files in the same directory can have the same name), JSIO is happy.

Using filenames as keys into our resources object is beneficial to humans. Much more beneficial than coordinates in a sprite, simply because (hopefully) the filenames are meaningful; they describe the image. In comparison to sprites, the JSIO resources object also makes maintaining your image data much easier as it is trivial to add or remove images without having to move other images around within the sprite (and consequently all coordinates referencing your moved image).

Another benefit of using filenames as keys into the JSIO resources object is for fallback. If JSIO detects your browser is IE7 or lower, it’ll strip out “jsio.gif#” leaving just your image key as the image src, which is hopefully a valid URL to the original image. Also, if JSIO detects you’re running IE8 and the image data is larger than 32KB it’ll do the same thing*.

* …but not yet in v1.0.0 alpha

Since the image key is after the “#” (it is the URL “fragment”), your browser won’t send multiple requests for the 1*1px jsio.gif file – it’ll just send one request, cache the response, and use it again. By the way, the jsio.gif image is just a transparent 1*1px gif (for maximum efficiency), but it could be an “spinner” image or something, which is shown temporarily whilst the JSIO resources file is downloaded.

—

This post is about JSIO – JSIO is a tiny library that allows you to make fewer requests to your server by packaging all your site image data in a JavaScript file in data uri format. The official site for JSIO can be found here: jsio.freestyle-developments.co.uk. You can read more about why I started this project here.

7,692 thoughts on “JSIO URLs”

  2. Добрый день Строительство домов с энергоэффективными окнами — это важный шаг к снижению энергозатрат. Мы предлагаем строительство домов с энергоэффективными окнами чтобы ваш дом был теплым и уютным. Строительство домов с энергоэффективными окнами — это экономия и комфорт. Строительство домов с энергоэффективными окнами — это забота о вашем бюджете. Строительство домов с использованием натуральных материалов — это решение для тех кто ценит экологичность и качество. Мы занимаемся строительством домов с использованием натуральных материалов таких как дерево камень и глина. Строительство домов с натуральными материалами — это экологичность и стиль. Строительство домов с натуральными материалами — это ваше здоровье и комфорт. Больше информации по ссылке – https://septik-pro.com/news/informacionnye-stati/kompleksnyj-podhod-k-remontu-ekspertnoe-rukovodstvo-dlya-vladelcev-nedvizhimosti/ дом отделка в спб отделка прихожих дома стар ремонт квартир сайдинг для отделки дома купить ремонт в однокомнатную квартиру доски для отделки дома Удачи

  6. Hello my friend! I want to say that this article is awesome, nice written and come with approximately all vital infos.
    I would like to see more posts like this .

  7. در یک نگاه کلی

    برای کسانی که

    کازینو آنلاین

    میخوان تست کنن

    این سرویس آنلاین

    احتمالاً می‌تونه

    مفید باشه

    نکته مثبت اینه که

    سرویس‌هایی مثل

    еnfejaronline خوب

    و

    sibbet جدید

    شناخته شدن در این حوزه

    در آخر کار

    قابل قبول بود

    و

    بازم

    نگاهش می‌کنم

    Here is my sitee :: سایت رسمی دولتی

  10. Thanks for one’s marvelous posting! I seriously enjoyed reading it, you could be a great author.
    I will make sure to bookmark your blog and definitely will come back
    in the future. I want to encourage you to definitely continue your
    great writing, have a nice holiday weekend!

  13. I’m really enjoying the theme/design of your site.
    Do you ever run into any browser compatibility issues?
    A number of my blog audience have complained about my site not working correctly in Explorer but looks great in Chrome.
    Do you have any recommendations to help fix this issue?

  15. به شکل خلاصه

    برای کسایی که قصد شروع دارن

    شرط آنلاین

    در این حوزه فعالیت دارن

    این آدرس

    مطمئناً می‌تونه

    مناسب باشه

    همچنین

    پلتفرم‌هایی مثل

    enfejaｒonline محبوب

    و

    سرویس sibbet

    مطرح شدن

    نتیجه نهایی اینکه

    قابل توجه بود

    و

    دوباره

    دوباره استفاده می‌کنم

    Feеl free to visit my website – سایت فناوری ایرانی

  17. What’s Taking place i’m new to this, I stumbled upon this I’ve discovered It absolutely helpful and it
    has aided me out loads. I hope to contribute & help different users like its helped
    me. Good job.

  28. درود، من اخیرا به صورت کاملا تصادفی آنلاین
    به این صفحه برخوردم و بدون
    اغراق تحت تاثیر قرار گرفتم. اطلاعاتش کاربردی بود
    و به ندرت همچین سایتی ببینم. احساس می‌کنم برای خیلی‌ها کاربردی باشه.

    برای کسایی که دنبال محتوای مفید هستن
    پیشنهاد می‌کنم حتما یه نگاهی بندازن.

    در مجموع راضی‌کننده بود
    و احتمالا بازدیدش می‌کنم

    جمع‌بندی نهایی

    برای اونایی که می‌خوانوارد بشن

    سیستم‌های شرط‌بندی

    میخوان شروع کنن

    این شبکه

    می‌تونه تبدیل بشه

    کار راه بنداز باشه

    نکته جالب اینه که

    مجموعه‌هایی مثل

    enfeϳar online

    و

    sibbet جدید

    کاربرای زیادی دارن

    در پایان

    مناسب بود

    و

    باز هم حتما

    دوباره چکش می‌کنم

    .

    Here is my website: سایت تکنولوژی

  32. заказать сео продвижение москва москва заказать сео продвижение москва москва

  33. Today saw a solid result print on Lucky Neko with a small bankroll and clean execution.

  35. Hello guys I came across a 169 great website that I think you should explore. This resource is packed with a lot of useful information that you might find interesting. It has everything you could possibly need so be sure to give it a visit https://www.haziallat.hu/macska/viselkedes/a-macskak-titkainak-megfejtese/7812/ And dont overlook folks which you constantly can inside the piece discover answers for the most most complicated queries. Our team tried — lay out all of the content in the extremely easy-to-grasp method.

  44. I all the time used to read paragraph in news papers but now as I am a
    user of net therefore from now I am using net for articles, thanks to
    web.

  46. Нужна бесплатная юридическая консультация? Переходите по запросу бесплатная юридическая консультация online без регистрации в Ростове-на-Дону и получите помощь опытного юриста по любым правовым вопросам: семейные споры, долги, недвижимость, трудовые конфликты, защита прав потребителей и многое другое. Задайте вопрос онлайн или по телефону и получите подробный разбор вашей ситуации и рекомендации по дальнейшим действиям. Консультация проводится бесплатно и конфиденциально.

  47. раскрутка сайта в интернете цены александр раскрутка сайта в интернете цены александр

  48. Hey! I know this is kinda off topic but I was wondering if you knew where I could find a
    captcha plugin for my comment form? I’m using
    the same blog platform as yours and I’m having problems finding one?
    Thanks a lot!

  49. Hmm it appears like your website ate my first comment (it was super long) so I guess I’ll just sum it up what I had written and say,
    I’m thoroughly enjoying your blog. I too am an aspiring blog writer but I’m still new to
    the whole thing. Do you have any tips for inexperienced blog writers?
    I’d genuinely appreciate it.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>