Not sure what is actually being asked - if you are asking whether you should get CHF before arriving in Switzerland, the answer depends on whether you get a better rate/fewer fees in the place you are coming from, versus using ATMs in Switzerland itself, which are widespread.
Nobody in Switzerland will refuse cash in payment so getting rid of cash is not a problem either.
Anyway in my view the value of CHF is only headed up in the long term, so holding on to excess is unlikely to be a losing proposition - especially since the Swiss National Bank has in the past few months adopted a policy that all Swiss banknotes from 1976 onwards will retain their monetary value indefinitely. Previously, the notes issued between 1976-1993 were due to become toilet paper 3 months from now, and the notes issued from 1994-2016 were likely to become toilet paper around the year 2040.
Oddly, plenty of Swiss ATMs also stock euros, and almost every train ticket machine takes euro notes at a rate which is not too bad. In the Geneva area, some machines even accept euro coins. I am not sure whether euros would be useful in a genuine emergency. But I did once buy 50 euros for 50 francs at Zurich airport from a Spanish guy who looked like he had some emergency going on (yes, it was a real banknote).