Check and uncheck anonymous access through the code

 Hi,
I need to check  anonymous access and uncheck anonymous access through the code. for example when i click a button anonymous access check box get checked and when i click on another button it gets uncheck. Is it possible to do with ASP.net?
(IIS - > righ click properties -> directory security - > anonymous access and authentication control - > Edit -> anonymous access check box)

Thankx. 

 
 
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