**快速入门**
#############################
使用S3 C# SDK前，您可以先参照 `API 手册 <../api/basicConcept.html>`_ 熟悉NOS的基本概念，如Bucket、Object、EndPoint、AccessKeyId和AccessKeySecret等。
本节您将看到如何快速的使用S3 C# SDK，完成常用的操作，上传文件、下载文件等。

常用类
=============================

====================== =========================================================
常用类                     备注                                                
====================== =========================================================
AmazonS3Client            NOS客户端类，用户通过AmazonS3Client调用服务 
AmazonException           NOS异常，在调用过程中去捕获这个异常，查看失败原因 
====================== =========================================================

基本操作
============================

上传文件
--------------------------------
对象（Object）是NOS中最基本的数据单元，您可以把它简单的理解为文件，以下代码可以实现简单的对象上传::

     public void PutObjectByFilePath(string bucket, string key, string filePath)
    {
        PutObjectRequest putObjectRequest = new PutObjectRequest()
        {
            BucketName = bucket,
            Key = key,
            FilePath = filePath,
        };

        try
        {
            PutObjectResponse resp = s3Client.PutObject(putObjectRequest);
        }
        catch (AmazonS3Exception ex)
        {
            Console.WriteLine("Failed with HTTPStatus: {0}; \nErrorCode: {1}; \nErrorMessage: {2}; \nRequestID:{3};",
            ex.StatusCode, ex.ErrorCode, ex.Message, ex.RequestId);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Failed with error info: {0}", ex.Message);
        }

    }

.. attention::

    1. 对象命名规则请参见 `API 手册 对象 <../api/basicConcept.html#id2>`_
    2. 更多的上传文件信息，请参见 `S3-C#-SDK 上传文件 <./uploadobject.html>`_

下载文件
------------------------------
上传对象成功之后，您可以读取它的内容，以下代码可以实现文件的下载::

    public void GetObject(string bucket,string key){
        GetObjectRequest request = new GetObjectRequest
        {
            BucketName = bucket,
            Key = key
        };
        try
        {
            using (GetObjectResponse response = s3Client.GetObject(request))
            {
                using (StreamReader reader = new StreamReader(response.ResponseStream))
                {
                    string contents = reader.ReadToEnd();
                    Console.WriteLine(" Object   - " + response.Key);
                    Console.WriteLine(" Contents - " + contents);
                }
            }

        } catch(AmazonS3Exception ex){
            Console.WriteLine("Failed with HTTPStatus: {0}; \nErrorCode: {1}; \nErrorMessage: {2}; \nRequestID:{3};",
            ex.StatusCode, ex.ErrorCode, ex.Message, ex.RequestId);
        } catch(Exception ex){
            Console.WriteLine("Failed with error info: {0}", ex.Message); 
        }

    }

更多的下载文件信息，请参见 `S3 C# SDK 下载文件 <./downloadobject.html>`_

列举文件
------------------------------
当上传文件成功之后，可以查看桶中包含的文件列表，以下代码展示如何列举桶内的文件::

    public void ListObjects(string bucketName){            
        try
        {
            var keys = new List<string>();
            ListObjectsResponse result = null;
            string nextMarker = string.Empty;
            do
            {
                var listObjectsRequest = new ListObjectsRequest()
                {
                    BucketName = bucketName,
                    Marker = nextMarker,
                    MaxKeys = 5
                };
                result = s3Client.ListObjects(listObjectsRequest);

                foreach (var obj in result.S3Objects)
                {
                    Console.WriteLine(obj.Key);
                }

                nextMarker = result.NextMarker;
            } while (result.IsTruncated);

            Console.WriteLine("List objects of bucket:{0} succeeded ", bucketName);
        }
        catch (AmazonS3Exception ex)
        {
            Console.WriteLine("Failed with HTTPStatus: {0}; \nErrorCode: {1}; \nErrorMessage: {2}; \nRequestID:{3};",
                ex.StatusCode, ex.ErrorCode, ex.Message, ex.RequestId);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Failed with error info: {0}", ex.Message);
        }
    }

.. note::

	1. 上面的代码默认列举100个object

更多的管理文件信息，请参见 `S3 C# SDK 文件管理 <./managerobject.html>`_

删除文件
------------------------------
文件上传成功后，可以指定删除桶中的文件，以下代码实现桶中文件的删除::

    public void DeleteObject(string bucketNaame, string key)
    {
        try
        {
            var resp = s3Client.DeleteObject(bucketNaame,key);
            Console.WriteLine("StatusCode : {0}", resp.HttpStatusCode);
        }
        catch (AmazonS3Exception ex)
        {
            Console.WriteLine("Failed with HTTPStatus: {0}; \nErrorCode: {1}; \nErrorMessage: {2}; \nRequestID:{3};",
                ex.StatusCode, ex.ErrorCode, ex.Message, ex.RequestId);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Failed with error info: {0}", ex.Message);
        }
    }


返回结果处理
------------------------------

S3 提供的所有接口都是有返回值的，如果你关心，那么就接住返回值，然后取你想要的信息，如果不关注，那么就不用获取

例如::

    try
    {
        var request = new CopyObjectRequest(){
            SourceBucket = sourceBucket,
            SourceKey = sourceKey,
            DestinationBucket = targetBucket,
            DestinationKey = targetKey
        };
        s3Client.CopyObject(request);
        Console.WriteLine("Copy object succeeded");
    }
    catch (AmazonS3Exception ex)
    {
        Console.WriteLine("Failed with HTTPStatus: {0}; \nErrorCode: {1}; \nErrorMessage: {2}; \nRequestID:{3};",
            ex.StatusCode, ex.ErrorCode, ex.Message, ex.RequestId);
    }
    catch (Exception ex)
    {
        Console.WriteLine("Failed with error info: {0}", ex.Message);
    }