Two questions that often arise when building Silverlight based websites are:
A. How do I detect if Silverlight is installed on a visitor’s browser?
B. How do I detect what version of Silverlight is installed on a visitor’s browser?
var isSLInstalled = Silverlight.isInstalled(null)
The answer to B is a little more complex since for some reason there is no direct way to get Silverlight’s version number. Basically the only documented way to answer this question is to repeatedly call isInstalled with different version numbers until you get the right version.
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