存UIImage

NSData *data2 = [[NSUserDefaults standardUserDefaults] objectForKey:@"imageKey"];

    UIImage *image2;

    if (data2) {

        image2 = [[UIImage alloc] initWithData:data2];

    } else {

        NSString *urlStr = @"http://124.254.4.114:10000/ask/3817bb85-6aa5-4388-83d4-4f63c104d1fc.jpeg";

        NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:urlStr]];

        image2 = [[UIImage alloc] initWithData:data];

        

        NSData *imageData = UIImageJPEGRepresentation(image2, 100);

        [[NSUserDefaults standardUserDefaults] setObject:imageData forKey:@"imageKey"];

        [[NSUserDefaults standardUserDefaults] synchronize];

    }

    

    UIImageView *imageView = [[UIImageView alloc] init];

    imageView.backgroundColor = [UIColor clearColor];

    imageView.frame = CGRectMake(0, 0, 100, 100);

    imageView.center = self.view.center;

    imageView.image = image2;

    [self.view addSubview:imageView];