instance method

Syntax

+ ( id ) instance

Remarks

Used as a global cache. To make HTTPRequests use it automatically, use [HTTPRequest setDefaultCache:[DownloadCache sharedCache]]; 
// assign the download cache to the request
[m_AsynchRequest setDownloadCache:[DownloadCache instance]];
// fine-tune cache settings
[m_AsynchRequest setCacheStoragePolicy:CachePermanently_CacheStoragePolicy];
Slightly more advanced technique 
// check for network reachability
int reachabilityStatus = [[Reachability reachabilityForInternetConnection] currentReachabilityStatus];
// use cached content if no network
if (reachabilityStatus == NotReachable) {
    [[DownloadCache instance] setDefaultCachePolicy:UseCacheIfLoadFails_CachePolicy];
}
else {
    [[DownloadCache instance] setDefaultCachePolicy:OnlyLoadIfNotCached_CachePolicy];
}