how to cache html5 File(UIWebView) - ios

Question

I use the UIWebView to load the URL which is a HTML5 application.
What I want to do is cache the HTML file,when there is no net connection,it load the cache.
when the connection can be use,it load the URL again to see if there has new data

Answer 1

you can try something like this:
#define APP_PATH_HTML_PAGES_CACHE [[NSHomeDirectory() stringByAppendingPathComponent:#"Library/Caches"] stringByAppendingPathComponent:#"html_pages_cache"]
- (void)setUrlString:(NSString *)urlString{
if (![_urlString isEqualToString:urlString]) {
NSURL *url = nil;
_urlString = urlString;
NSString *fileName = [self fileNameFromUrl:_urlString];
if(isInternetConnected){//load page and store on file system
url = [NSURL URLWithString:_urlString];
[self downloadPageWithName:fileName andUrl:url];//download to cache
}else{
//network is not available, check for cached file
if ([self isFileExistInCacheDirectory:fileName]) {
url = [NSURL fileURLWithPath:[APP_PATH_HTML_PAGES_CACHE stringByAppendingPathComponent:fileName]];
}
else {
//TODO: show offline/error alert
}
}
//load local or remote page
// here url can point to local file or web page
NSURLRequest* request = [[NSURLRequest alloc]initWithURL:url];
//to be sure that view components did initialized.
if ([self view]) {
[self.webView loadRequest:request];
}
}
- (void)downloadPageWithName:(NSString*)fileName andUrl:(NSURL*)url
{
`dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[self checkIsCacheDirectoryExistOrCreate];`
NSString *filePath = [APP_PATH_HTML_PAGES_CACHE stringByAppendingPathComponent:fileName];
NSData *data = [NSData dataWithContentsOfURL:url];
[data writeToFile:filePath atomically:YES];
NSLog(#"Download: %# -> %#", url.absoluteString, filePath);
});
}