Client-Side AJAX files
If you installed the MS AJAX at its default location, you can find six .js files in the following location:
C:\Program Files\Microsoft ASP.NET\ASP.NET 2.0 AJAX Extensions\v1.0.61025\MicrosoftAjaxLibrary\System.Web.Extensions?.0.61025.0
On the production (release) environments the above js files get downloaded to the client machine. However, since they are stripped off all the comments and line breaks, they are not read-friendly. However, if you want to read and understand these files, you can open up the debug versions of these files in the same directory:
The size of the release version of these files (i.e. the comments stripped and line breaks taken out) is reduced by 50-67% over the size of the debug version. The sizes of the debug and release versions of these files are shown below:
MicrosoftAjax.js 254KB vs. 82KB (67% reduction)
MicrosoftAjaxTimer.js 6KB vs. 3KB (50% reduction)
MicrosoftAjaxWebForms.js 65KB vs. 29KB (55% reduction)
Removing the newline/linebreak characters not only reduces the size of the file, it also makes it difficult to the power user / another developer ‘reverse-engineer’ your code. If you open the release version of MicrosoftAjax.js file, the first code line stretches on to 80 thousand characters. Without a lot of time in one’s hands, it would be difficult to make sense of the code (Obviously, the obfuscation is not the aim in case of Microsoft Ajax library – the fully-documented source code is available).
C:\Program Files\Microsoft ASP.NET\ASP.NET 2.0 AJAX Extensions\v1.0.61025\Source
How does the MicrosoftAjax.js provide the basic AJAX functionality?