Objective-C:

#import <DPLocalCache.h>
...
- (void)viewDidLoad {
    //Any place to add only once!!!
    //添加浏览器本地缓存处理
    DPLocalCache *urlCache = [[DPLocalCache alloc] initWithMemoryCapacity:20 * 1024 * 1024
                                                             diskCapacity:200 * 1024 * 1024
                                                                 diskPath:nil
                                                                cacheTime:60*60*24
                                                                 modeTybe:DOWNLOAD_MODE
                                                             subDirectory:@"PXPT"];
    [NSURLCache setSharedURLCache:urlCache];
}
- (void)didReceiveMemoryWarning{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.

    //Any place to add only once!!!
    DPLocalCache *urlCache = (DPLocalCache *)[NSURLCache sharedURLCache];
    [urlCache removeAllCachedResponses];
}
...