You can use the client and server to determine if the client is installed .NET framework, one is to determine whether the string returned by the client Navigator.USERAGENT includes the value describing the .NET framework. The server-side method is to use Request.ServerVariables ["http_user_agent"]. TOSTRING (); to return a string, the strings returned by both are the same. The returned string of the .NET frame is (take my machine as an example): Mozilla / 4.0 (Compatible; Msie 6.0; Windows NT 5.0; .NET CLR 1.1.4322) The string of the .NET framework is: Mozilla / 4.0 (Compatible; Msie 6.0; Windows NT 5.0)
If you feel that you write the code very troublesome, you can also pay "probes" online, then download it later. I am the first to study the source code of the probe.
