阿里云OSS存储

1.accessKeyId 与 accessKeySecret 是由系统分配给用户的，称为ID对，用于标识用户，为访问OSS做签名验证。

2.Bucket是OSS上的命名空间，相当于数据的容器，可以存储若干数据实体（Object）

你可以按照下面的代码新建一个Bucket：

        /// <summary>
        /// 新建存储对象容器Bucket
        /// </summary>
        /// <param name="bucketName">容器名称</param>
        void CreateBucket(string bucketName)
        {
            //初始化 OSSClient
            OssClient ossClient = new OssClient(endPoint, accessKeyId, accessKeySecret);

            // 新建一个Bucket
            var bucket = ossClient.CreateBucket(bucketName);

            Console.WriteLine(bucket.CreationDate);
        }

由于Bucket的名字是全局唯一的，所以尽量保证你的 bucketName 不与别人重复。

其实也可以在阿里云的OSS管理控制台创建。

public class OssUtils {

    private static String endpoint = "";
    private static String accessKeyId = "";
    private static String accessKeySecret = "";
    private static String bucketName = "";

    /**
     * oss 下载文件
     * 
     * @param ossKey
     * @return
     */
    public static File downLoadFile(String ossKey) throws Exception {
        OSSClient ossClient = new OSSClient(endpoint, accessKeyId, accessKeySecret);
        try {
            // 判断Bucket是否存在。详细请参看“SDK手册 > Java-SDK > 管理Bucket”。
            if (ossClient.doesBucketExist(bucketName)) {
                // 先将文件写入临时文件再下载
                String filename = "temp" + ossKey.substring(ossKey.lastIndexOf("."), ossKey.length());
                File f = new File(filename);
                ossClient.getObject(new GetObjectRequest(bucketName, ossKey), f);
                return f;
            }
            return null;
        } catch (Exception e) {
            throw e;
        } finally {
            ossClient.shutdown();
        }
    }

    /**
     * 上传文件到OSS
     * 
     * @param ossKey
     * @param f
     * @throws Exception
     */
    public static void uploadFIle(String ossKey, File f) throws Exception {
        OSSClient ossClient = new OSSClient(endpoint, accessKeyId, accessKeySecret);
        try {
            // 判断Bucket是否存在。详细请参看“SDK手册 > Java-SDK > 管理Bucket”。
            if (ossClient.doesBucketExist(bucketName)) {
                ObjectMetadata meta = new ObjectMetadata();
                // 设置自定义元信息name的值为my-data
                meta.addUserMetadata("Content-Type", "application/octet-stream");
                meta.addUserMetadata("Content-Disposition", "attachment;filename=" + ossKey);
                InputStream inputStream = new FileInputStream(f);
                // 上传
                ossClient.putObject(bucketName, ossKey, inputStream);
                inputStream.close();

                // 转换pdf文件
//                ChangeFile(f, ossKey);
            }
        } catch (Exception e) {
            throw e;
        } finally {
            ossClient.shutdown();
        }
    }

}