将图片保存到沙盒或者相册

将图片保存到沙盒或者相册：
1.保存到相册：

-(void)saveImageToAlbum:(UIButton *)sender{
    //将图片保存到相册中
    UIImageWriteToSavedPhotosAlbum(self.image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
}

2.保存到沙盒中

-(void)saveImageToSandBox:(UIButton *)sender{

    //将图片保存到沙盒
    //保存文件到沙盒
    //获取沙盒中Documents目录路径
// NSString *documents = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];

// NSLog(@"%@",documents);

NSString *documents = [NSHomeDirectory() stringByAppendingPathComponent:@"/Documents"];

    NSLog(@"%@",documents);
    //拼接文件绝对路径
    NSString *path = [documents stringByAppendingPathComponent:self.fileName];

    //保存
    [self.results writeToFile:path atomically:YES];
}

//不管保存成功与失败都回调用该方法

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo{

    if (error != nil) {
        UIAlertView *fail = [[UIAlertView alloc]initWithTitle:@"提示" message:@"保存失败" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];
        [fail show];
        NSLog(@"%@",error);
    }
    else{
        UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"保存成功" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];

        [alert show];
        [self.view addSubview:alert];
    }
}