專案中需要新增以下依賴項，在控制檯中執行安裝依賴項：

Install-Package Aliyun.OSS.SDK --適用於.NET版本
Install-Package Aliyun.OSS.SDK.NetCore --適用.NET Core版本

以下是封裝的上傳下載以及生成圖片連結的方法：

/// <summary>
/// 上傳檔案
/// </summary>
/// <param name="accessKeyId">開發者祕鑰對，通過阿里雲控制檯的祕鑰管理頁面建立與管理</param>
/// <param name="accessKeySecret">開發者祕鑰對，通過阿里雲控制檯的祕鑰管理頁面建立與管理</param>
/// <param name="endpoint">Endpoint，建立Bucket時對應的Endpoint</param>
/// <param name="bucketName">Bucket名稱，建立Bucket時對應的Bucket名稱</param>
/// <param name="key">檔案標識</param>
/// <param name="file">需要上傳檔案的檔案路徑</param>
public static void PutObject(string accessKeyId, string accessKeySecret, string endpoint, string bucketName, string key, string file)
{
    var client = new OssClient(endpoint, accessKeyId, accessKeySecret);
    try
    {
        client.PutObject(bucketName, key, file);
    }
    catch (OssException ex)
    {
        LogHelper.LogException<OssException>(
            $"Msg:{ex.Message};Code:{ex.ErrorCode};RequestID:{ex.RequestId};HostID:{ex.HostId}");
    }
}

/// <summary>
/// 下載檔案
/// </summary>
/// <param name="accessKeyId">開發者祕鑰對，通過阿里雲控制檯的祕鑰管理頁面建立與管理</param>
/// <param name="accessKeySecret">開發者祕鑰對，通過阿里雲控制檯的祕鑰管理頁面建立與管理</param>
/// <param name="endpoint">Endpoint，建立Bucket時對應的Endpoint</param>
/// <param name="bucketName">Bucket名稱，建立Bucket時對應的Bucket名稱</param>
/// <param name="key">檔案標識</param>
/// <param name="file">下載存放的檔案路徑</param>
public static void GetObject(string accessKeyId, string accessKeySecret, string endpoint, string bucketName, string key, string file)
{
    var client = new OssClient(endpoint, accessKeyId, accessKeySecret);
    try
    {
        var result = client.GetObject(bucketName, key);
        using (var requestStream = result.Content)
        {
            using (var fs = File.Open(file, FileMode.OpenOrCreate))
            {
                int length = 4 * 1024;
                var buf = new byte[length];
                do
                {
                    length = requestStream.Read(buf, 0, length);
                    fs.Write(buf, 0, length);
                } while (length != 0);
            }
        }
    }
    catch (OssException ex)
    {
        LogHelper.LogException<OssException>(
            $"Msg:{ex.Message};Code:{ex.ErrorCode};RequestID:{ex.RequestId};HostID:{ex.HostId}");
    }
}

/// <summary>
/// 獲取圖片地址
/// </summary>
/// <param name="accessKeyId">開發者祕鑰對，通過阿里雲控制檯的祕鑰管理頁面建立與管理</param>
/// <param name="accessKeySecret">開發者祕鑰對，通過阿里雲控制檯的祕鑰管理頁面建立與管理</param>
/// <param name="endpoint">Endpoint，建立Bucket時對應的Endpoint</param>
/// <param name="bucketName">Bucket名稱，建立Bucket時對應的Bucket名稱</param>
/// <param name="key">檔案標識</param>
/// <param name="width">設定圖片的寬度</param>
/// <param name="height">設定圖片的高度</param>
/// <returns></returns>
public static string GetIamgeUri(string accessKeyId, string accessKeySecret, string endpoint, string bucketName, string key, float width = 100, float height = 100)
{
    var client = new OssClient(endpoint, accessKeyId, accessKeySecret);
    try
    {
        var process = $"image/resize,m_fixed,w_{width},h_{height}";
        var req = new GeneratePresignedUriRequest(bucketName, key, SignHttpMethod.Get)
        {
            Expiration = DateTime.Now.AddHours(1),
            Process = process
        };
        var uri = client.GeneratePresignedUri(req);
        return uri.ToString();
    }
    catch (OssException ex)
    {
        LogHelper.LogException<OssException>(
            $"Msg:{ex.Message};Code:{ex.ErrorCode};RequestID:{ex.RequestId};HostID:{ex.HostId}");
    }
}
 

呼叫方法：

var accessKeyId = "";
var accessKeySecret = "";
var endpoint = "oss-cn-shenzhen.aliyuncs.com";
var bucketName = "service-img";

// 上傳檔案
OssApi.PutObject(accessKeyId, accessKeySecret, endpoint, bucketName, "2019012215062801", "C:/Users/as/Desktop/2019012215062801.png");

// 下載檔案
OssApi.GetObject(accessKeyId, accessKeySecret, endpoint, bucketName, "2019012215062801", "C:/Users/as/Desktop/down.png");

// 獲取圖片連結地址
OssApi.GetIamgeUri(accessKeyId, accessKeySecret, endpoint, bucketName, "2019012215062801", 100, 100);