cookie清除
NSHTTPCookie *cookie;
NSHTTPCookieStorage *storage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (cookie in [storage cookies])
{
[storage deleteCookie:cookie];
}
缓存 清除
[[NSURLCache sharedURLCache] removeAllCachedResponses];
原文:http://www.cnblogs.com/wlsxmhz/p/5434046.html