在UIWebView下，可以使用
[[NSURLCache sharedURLCache] removeAllCachedResponses];//清除缓存
当使用wkwebview时候WKWebView清除cookies的方法（iOS9以上）
WKWebsiteDataStore *dateStore = [WKWebsiteDataStore defaultDataStore];
[dateStore fetchDataRecordsOfTypes:[WKWebsiteDataStore allWebsiteDataTypes]
completionHandler:^(NSArray * __nonnull records) {
for (WKWebsiteDataRecord *record in records)
{
// if ( [record.displayName containsString:@"baidu"]) //取消备注，可以针对某域名清除，否则是全清
// {
[[WKWebsiteDataStore defaultDataStore] removeDataOfTypes:record.dataTypes
forDataRecords:@[record]
completionHandler:^{
NSLog(@"Cookies for %@ deleted successfully",record.displayName);
}];
// }
}
}];
iOS9一下用这种方法：
NSString *libraryPath = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *cookiesFolderPath = [libraryPath stringByAppendingString:@"/Cookies"];
NSError *errors;
[[NSFileManager defaultManager] removeItemAtPath:cookiesFolderPath error:&errors];
查看cookie
NSHTTPCookie *cookie;
NSHTTPCookieStorage *cookieJar = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (cookie in [cookieJar cookies]) {
NSLog(@"%@", cookie);
}
