NSHTTPCookieStorage *cookieStorage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (NSHTTPCookie *each in cookieStorage.cookies) {
[cookieStorage deleteCookie:each];
NSHTTPCookieStorage *cookieStorage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (NSHTTPCookie *each in cookieStorage.cookies) {
[cookieStorage deleteCookie:each];