网络---小文件的下载

dispatch_async(dispatch_get_global_queue(0, 0), ^{

NSURL *url = [NSURL URLWithString:@"下载地址”];
NSData *data = [NSData dataWithContentsOfURL:url];
NSLog(@"%d", data.length);
});

NSURL *url = [NSURL URLWithString:@"下载地址"];

NSURLRequest *request = [NSURLRequest requestWithURL:url];

[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
NSLog(@"%d", data.length);
}];