Traveling to Switzerland with stay permit and schengen visa

Update: Now Switzerland is in Schengen area and issues a swiss visa, Now you CAN travel to swiss if you have
1. Schengen Visa OR
2. Valid Residence permit issued by EEA countries.

For details
http://www.bfm.admin.ch/bfm/en/home/themen/einreise/schengen-visum.html

Earlier Switzerland was neither an EU country nor a Schengen country, it has recently signed the agreement would are free.

To simplify, I will discuss it in two steps.

Having schengen visa.
You CAN travel to swiss with schengen visa and also you CAN transit with your schengen visa.

Having Valid Stay permit.
If you have valid Stay permit issued by any of the schengen coutry, then you CAN travel to Switzerland without any problem

Keep in mind that if you have applied for your stay permit, like permesso di soggiorno in Italy and you have the Italian post ricevuta, then you CAN NOT travel.

Please note that the link provided above it the official website of swissm, Federal Administration, Federal Department of Justice and Police, Federal Office for Migration.

Have a nice travel to Switzerland.