CDNs (Content Delivery Networks) are great to speed up website performances, but they are a mess when you are testing your website on your development machine.
Another problem may arise if you want to change your CDN to another one. Do yoy have to replace all URLs in all your pages?
In this article I'll show you a clever and definitive solution to avoid hardcoding the CDN URLs in your HTML markup.

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There is a well-known bug on Internet Explorer 10 for WIndows Phone 8 that avoids responsive web sites to display correctly. The cause is that Internet Explorer 10 doesn't differentiate device width from viewport width, and thus doesn't properly apply the media queries in your favorite responsive CSS framework.
You can find many fixes on the client side, but if you're using ASP.NET, you have the chance to fix it server side with only few lines of code.

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Lazy loading applied to a web page is an excellent technique when all contents aren't immediately visible and you want to speed up page rendering.
A perfect candidate for this method are image galleries with many items, only the first image is visible when the page loads, other images will be visible only if the user decides to browse them.
This technique sounds great, but has a big SEO problem: search engine crawlers does not execute scripts, they only analyze HTML markup, so all the code that renders images dynamically is totally ignored along with images and captions.

Here're four solutions and, as often happens, the best is the last one.

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In questo articolo vedremo come controllare con precisione la cache del client (il browser del vostro PC ad esempio) in modo da evitare di trasmettere dati dal server quando il client già li possiede. Il server ASP.NET già possiede dei sistemi di caching dei dati, ad esempio per evitare di continuare ad eseguire la stessa query nel database; ma sti dati, non sarebbe bello evitare di trasmetterli, risparmiando il consumo di banda?

La tecnica si chiama GET condizionale ed utilizza l'HTTP status code 304 ed è particolarmente utile quando i dati sono generati dinamicamente lato server e cambiano durante il tempo.

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Have you changed your domain and don't want to loose your SEO page rankings?
Do you have renamed a page and don't want to return errors to users that have saved a bookmark?
You have to perform a 301 permanent redirect to the new page/site.

There are plenty of methods to perform this, if you Google the question you'll be submerged by the answers.
Curiously the easiest method doesn't come out first.

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