# .NET SDK
本章节介绍.NET SDK，您可以参考本章节进行快速集成开发。
 #### 准备工作
- [注册华为账号并开通华为云](https://support.huaweicloud.com/usermanual-account/account_id_001.html)，并完成实名认证，账号不能处于欠费或冻结状态。
- 已具备开发环境，.NET SDK 适用于.NET Standard 2.0 及其以上版本；C# 4.0 及其以上版本。
- 登录"[我的凭证](https://console.huaweicloud.com/iam/#/myCredential) \> 访问密钥"页面，获取Access Key（AK）和Secret Access Key（SK）。
  图1获取AK、SK   
  ![](https://support.huaweicloud.com/sdkreference-face/zh-cn_image_0000001731915448.png "点击放大") 
- 登录"[我的凭证](https://console.huaweicloud.com/iam/#/myCredential)"页面，获取"IAM用户名"、"账号名"以及待使用区域的"项目ID"。调用服务时会用到这些信息，请提前保存。
  本样例以"华北-北京四"区域为例，获取对应的项目ID（project_id）。
  图2我的凭证   
  ![](https://support.huaweicloud.com/sdkreference-face/zh-cn_image_0000001779403629.png "点击放大") 
 
#### 安装SDK
使用SDK前，需要安装"HuaweiCloud.SDK.Core"和"HuaweiCloud.SDK.Frs"，有两种安装方式，分别如下。
- 使用 .NET CLI 工具
  ```
  dotnet add package HuaweiCloud.SDK.Core
  dotnet add package HuaweiCloud.SDK.Frs
  ```
  
- 使用 Package Manager
  ```
  Install-Package HuaweiCloud.SDK.Core
  Install-Package HuaweiCloud.SDK.Frs
  ```
  
 
#### 开始使用
在开始使用之前，请确保您安装的是最新版本的SDK。使用过时的版本可能会导致兼容性问题或无法使用最新功能。您可以通过运行以下命令来检查并更新SDK至最新版本。
```
dotnet list package
dotnet add package HuaweiCloud.SDK.Core --version *
dotnet add package HuaweiCloud.SDK.Frs --version *
```
详细的SDK介绍，使用异步客户端，配置日志等操作请参见[SDK中心](https://sdkcenter.developer.huaweicloud.com/)、[.NET SDK使用指导](https://github.com/huaweicloud/huaweicloud-sdk-net-v3/blob/master/README_CN.md)、[.NET SDK视频指导](https://res-video.hc-cdn.com/cloudbu-site/china/zh-cn/support/sdk-video/huaweicloud_.net_sdk.mp4)。
1. 导入依赖模块
   ```
   using System;
   using System.Collections.Generic;
   using HuaweiCloud.SDK.Core;
   using HuaweiCloud.SDK.Core.Auth;
   using HuaweiCloud.SDK.Frs;
   using HuaweiCloud.SDK.Frs.V2;
   using HuaweiCloud.SDK.Frs.V2.Model;
   ```
   
2. 配置客户端连接参数
   - 默认配置
     ```
     // 使用默认配置
     var config = HttpConfig.GetDefaultConfig();
     ```
     
   
   - 网络代理（可选）
     ```
     // 根据需要配置网络代理
     config.ProxyHost = "proxy.huaweicloud.com";
     config.ProxyPort = 8080;
     config.ProxyUsername = "test";
     config.ProxyPassword = "test";
     ```
     
   
   - 超时配置（可选）
     ```
     // 默认超时时间为120秒，可根据需要调整
     config.Timeout = 120;
     ```
     
   
   - SSL配置（可选）
     ```
     // 根据需要配置是否跳过SSL证书验证
     config.IgnoreSslVerification = true;
     ```
     
    
3. 配置认证信息 配置AK、SK信息。华为云通过AK识别用户的身份，通过SK对请求数据进行签名验证，用于确保请求的机密性、完整性和请求者身份的正确性。AK、SK获取方法请参见[准备工作]。
   ```
   const string ak = Environment.GetEnvironmentVariable("HUAWEICLOUD_SDK_AK");
   const string sk = Environment.GetEnvironmentVariable("HUAWEICLOUD_SDK_SK");
   var auth = new BasicCredentials(ak, sk);
   ```
   ![](https://support.huaweicloud.com/sdkreference-face/public_sys-resources/caution_3.0-zh-cn.png)
   - 认证用的 ak 和sk 硬编码到代码中或者明文存储都有很大的安全风险，建议在配置文件或者环境变量中密文存放，使用时解密，确保安全。
   
   - 本示例以 ak 和 sk 保存在环境变量中来实现身份验证为例，运行本示例前请先在本地环境中设置环境变量HUAWEICLOUD_SDK_AK和HUAWEICLOUD_SDK_SK。
    
   图3Windows环境新建环境变量   
   ![](https://support.huaweicloud.com/sdkreference-face/zh-cn_image_0000001732268862.png "点击放大") 
4. 初始化客户端
   - 指定云服务region方式（推荐）
     ```
     // 初始化指定云服务的客户端 {Service}Client ，以初始化FRS服务的 FrsClient 为例
     var client = FrsClient.NewBuilder()
             .WithCredential(auth)
             .WithRegion(FrsRegion.ValueOf("cn-north-4"))
             .WithHttpConfig(config)
             .Build();
     ```
     
   
   - 指定云服务endpoint方式
     ```
     // 指定终端节点，以FRS服务北京四的 endpoint 为例
     String endpoint = "https://face.cn-north-4.myhuaweicloud.com";
     // 初始化客户端认证信息，需要填写相应 projectId，以初始化 BasicCredentials 为例
     var auth = new BasicCredentials(ak, sk, projectId);
     // 初始化指定云服务的客户端 {Service}Client，以初始化FRS服务的 FrsClient 为例
     var client = FrsClient.NewBuilder()
         .WithCredential(auth)
         .WithEndPoint(endpoint)
         .WithHttpConfig(config)
         .Build();
     ```
     endpoint是华为云各服务应用区域和各服务的终端节点，详情请查看 [地区和终端节点](https://developer.huaweicloud.com/endpoint?FRS) 。
     
    
5. 发送请求并查看响应
   ```
   // 以调用人脸检测接口 DetectFaceByBase64 为例
   var req = new DetectFaceByBase64Request
   {
   };
   req.Body = new FaceDetectBase64Req()
   {
       ImageBase64 = "图片的base64编码"
    };
   try
   {
       var resp = client.DetectFaceByBase64(req);
       var respStatusCode = resp.HttpStatusCode;
       Console.WriteLine(respStatusCode);
   }
   ```
   ![](https://support.huaweicloud.com/sdkreference-face/public_sys-resources/note_3.0-zh-cn.png)
   使用人脸比对SDK时，image1、image2参数需为相同类型，即同为url、base64或file。
   
6. 异常处理
   表1异常处理 
   | 一级分类                     | 一级分类说明  | 二级分类                     | 二级分类说明                      |
   |:---|:---|:---|:---|
   | ConnectionException      | 连接类异常   | HostUnreachableException | 网络不可达、被拒绝。                  |
   | ConnectionException      | 连接类异常   | SslHandShakeException    | SSL认证异常。                    |
   | RequestTimeoutException  | 响应超时异常  | CallTimeoutException     | 单次请求，服务器处理超时未返回。            |
   | RequestTimeoutException  | 响应超时异常  | RetryOutageException     | 在重试策略消耗完成后，仍无有效的响应。         |
   | ServiceResponseException | 服务器响应异常 | ServerResponseException  | 服务端内部错误，Http响应码：\[500,\]。   |
   | ServiceResponseException | 服务器响应异常 | ClientRequestException   | 请求参数不合法，Http响应码：\[400, 500) |
      
   ```
   // 捕获和处理不同类型的异常
   try
   {
       var resp = client.DetectFaceByBase64(req);
       var respStatusCode = resp.HttpStatusCode;
       Console.WriteLine(respStatusCode);
   }
   catch (RequestTimeoutException requestTimeoutException)
   {
       Console.WriteLine(requestTimeoutException.ErrorMessage);
   }
   catch (ServiceResponseException clientRequestException)
   {
       Console.WriteLine(clientRequestException.HttpStatusCode);
       Console.WriteLine(clientRequestException.ErrorCode);
       Console.WriteLine(clientRequestException.ErrorMsg);
    }
   catch (ConnectionException connectionException)
   {
       Console.WriteLine(connectionException.ErrorMessage);
   }
   ```
   
 
#### SDK demo代码解析
- 人脸检测
  ```
  var req = new DetectFaceByBase64Request
              {
              };
              req.Body = new FaceDetectBase64Req()
              {
                  ImageBase64 = "图片的base64编码"
              };
  try
              {
  var resp = client.DetectFaceByBase64(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 人脸比对
  ```
  var req = new CompareFaceByBase64Request
              {
              };
              req.Body = new FaceCompareBase64Req()
              {
                  Image1Base64 = "图片1的base64编码",
                  Image2Base64 = "图片2的base64编码"
              };
  try
              {
  var resp = client.CompareFaceByBase64(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 人脸搜索
  ```
  var req = new SearchFaceByBase64Request
              {
              };
              req.Body = new FaceSearchBase64Req()
              {
                  ImageBase64 = "图片的base64编码"
              };
  try
              {
  var resp = client.SearchFaceByBase64(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 创建人脸库
  ```
  var req = new CreateFaceSetRequest
              {
              };
              req.Body = new CreateFaceSetReq()
              {
                  FaceSetName = "人脸库名称"
              };
  try
              {
  var resp = client.CreateFaceSet(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 查询人脸库
  ```
  var req = new ShowFaceSetRequest
              {
                  FaceSetName = "人脸库名称"
              };
  try
              {
  var resp = client.ShowFaceSet(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 查询所有人脸库
  ```
  var req = new ShowAllFaceSetsRequest
              {
              };
  try
              {
  var resp = client.ShowAllFaceSets(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 删除人脸库
  ```
  var req = new DeleteFaceSetRequest
              {
                  FaceSetName = "人脸库名称"
              };
  try
              {
  var resp = client.DeleteFaceSet(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 添加人脸
  ```
  var req = new AddFacesByBase64Request
              {
              };
              req.Body = new AddFacesBase64Req()
              {
                  ImageBase64 = "图片的base64编码"
              };
  try
              {
  var resp = client.AddFacesByBase64(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 删除人脸
  ```
  var req = new DeleteFaceByFaceIdRequest
              {
                  FaceSetName = "人脸库名称",
                  FaceId = "人脸ID"
              };
  try
              {
  var resp = client.DeleteFaceByFaceId(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 批量删除人脸
  ```
  var req = new BatchDeleteFacesRequest
              {
              };
              req.Body = new DeleteFacesBatchReq()
              {
                  Filter = "过滤条件"
              };
  try
              {
  var resp = client.BatchDeleteFaces(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 更新人脸
  ```
  var req = new UpdateFaceRequest
              {
              };
              req.Body = new UpdateFaceReq()
              {
                  FaceId = "人脸库ID"
              };
  try
              {
  var resp = client.UpdateFace(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
          }
  ```
  
- 查询人脸
  ```
  var req = new ShowFacesByFaceIdRequest
              {
                  FaceSetName = "人脸库名称",
                  FaceId = "人脸ID"
              };
  try
              {
  var resp = client.ShowFacesByFaceId(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 动作活体检测
  ```
  var req = new DetectLiveByBase64Request
              {
              };
              req.Body = new LiveDetectBase64Req()
              {
                  Actions = "动作代码顺序列表",
                  VideoBase64 = "视频数据的base64编码"
              };
  try
              {
  var resp = client.DetectLiveByBase64(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
- 静默活体检测
  ```
  var req = new DetectLiveFaceByBase64Request
              {
              };
              req.Body = new LiveDetectFaceBase64Req()
              {
                  ImageBase64 = "图片的base64编码"
              };
  try
              {
  var resp = client.DetectLiveFaceByBase64(req);
  var respStatusCode = resp.HttpStatusCode;
                  Console.WriteLine(respStatusCode);
              }
  catch (RequestTimeoutException requestTimeoutException)
              {
                  Console.WriteLine(requestTimeoutException.ErrorMessage);
              }
  catch (ServiceResponseException clientRequestException)
              {
                  Console.WriteLine(clientRequestException.HttpStatusCode);
                  Console.WriteLine(clientRequestException.ErrorCode);
                  Console.WriteLine(clientRequestException.ErrorMsg);
              }
  catch (ConnectionException connectionException)
              {
                  Console.WriteLine(connectionException.ErrorMessage);
              }
  ```
  
 
#### SDK代码自动生成
[API Explorer](https://apiexplorer.developer.huaweicloud.com/apiexplorer/sdk?product=FRS&api=DetectFaceByBase64)提供API检索及平台调试，支持全量快速检索、可视化调试、帮助文档查看和在线咨询。
您只需要在API Explorer中修改接口参数，即可自动生成对应的代码示例。
图4API Explorer   
![](https://support.huaweicloud.com/sdkreference-face/zh-cn_image_0000001207659004.png "点击放大")