小文件下载

- (void)downloadFile
{
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        // 其实这就是一个GET请求
        NSURL *url = [NSURL URLWithString:@"http://localhost:8080/MJServer/resources/images/minion_01.png"];
        NSData *data = [NSData dataWithContentsOfURL:url];
        NSLog(@"%d", data.length);
    });
}

// 2.NSURLConnection
- (void)downloadFile2
{
    NSURL *url = [NSURL URLWithString:@"http://localhost:8080/MJServer/resources/images/minion_01.png"];
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
        NSLog(@"%d", data.length);
    }];
}