C#调用Google Sheets API获取凭证时遇「无法识别凭证类型」错误求助

使用Google API获取凭证时遇到问题，查阅大量旧帖仍未找到解决方案，目标是将指定电子表格中的数据导入到DataTable中。

我的代码 #

static readonly string[] Scopes = { SheetsService.Scope.Spreadsheets };
static readonly string ApplicationName = "Dot Tutorials";
static readonly string sheet = "Arkusz1";
static readonly string SpreadsheetId = "1IEvv4enfouBXrGEVLTKeQNYTJIzQHmRNyKTxKAxEAfg";
static SheetsService service;
GoogleCredential credential;
    //Reading Credentials File...
    using (var stream = new FileStream("secret.json", FileMode.Open, FileAccess.Read))
    {
        credential = GoogleCredential.FromStream(stream)
            .CreateScoped(Scopes);
    }
    // Creating Google Sheets API service...
    service = new SheetsService(new BaseClientService.Initializer()
    {
        HttpClientInitializer = credential,
        ApplicationName = ApplicationName,
    });

下载的secret.json内容 #

{
  "installed": {
    "client_id": "1087609048092-hdh5ku57kaamha72o7t3tdtkb62vq5ur.apps.googleusercontent.com",
    "project_id": "excellent-well-151116",
    "auth_uri": "https://accounts.google.com/o/oauth2/auth",
    "token_uri": "https://oauth2.googleapis.com/token",
    "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
    "client_secret": "*********hidden my secret code*******",
    "redirect_uris": [
      "http://localhost"
    ]
  }
}

运行时错误 #

System.InvalidOperationException: 'Error creating credential from JSON or JSON parameters. Unrecognized credential type .'

解决方案 #

你的secret.json是桌面应用类型的OAuth客户端凭证（包含installed字段），这类凭证不能直接通过GoogleCredential.FromStream初始化，因为它需要走OAuth 2.0授权码流程获取用户授权令牌，而非服务账号的直接认证方式。

修改后的代码

static readonly string[] Scopes = { SheetsService.Scope.Spreadsheets };
static readonly string ApplicationName = "Dot Tutorials";
static readonly string sheet = "Arkusz1";
static readonly string SpreadsheetId = "1IEvv4enfouBXrGEVLTKeQNYTJIzQHmRNyKTxKAxEAfg";
static SheetsService service;

// 处理用户授权并获取凭证
UserCredential credential;
using (var stream = new FileStream("secret.json", FileMode.Open, FileAccess.Read))
{
    // 指定令牌缓存路径，避免重复授权
    string credPath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Personal), ".credentials/sheets-dotnet-tutorial.json");
    credential = GoogleWebAuthorizationBroker.AuthorizeAsync(
        GoogleClientSecrets.FromStream(stream).Secrets,
        Scopes,
        "user",
        CancellationToken.None,
        new FileDataStore(credPath, true)).Result;
}

// 创建Sheets服务实例
service = new SheetsService(new BaseClientService.Initializer()
{
    HttpClientInitializer = credential,
    ApplicationName = ApplicationName,
});

额外注意事项

1. NuGet包检查：确保项目已安装Google.Apis.Sheets.v4和Google.Apis.Auth两个NuGet包，版本保持一致。
2. 文件路径设置：将secret.json的属性设置为「复制到输出目录」（如果文件不在程序运行目录下），确保程序能读取到该文件。
3. 电子表格权限：确保你的Google账号有权访问目标电子表格，可通过共享功能将表格权限开放给该账号，或设置表格为公开可查看/编辑。
4. 授权流程：第一次运行代码会弹出浏览器，引导你登录Google账号并授权应用访问Sheets数据，授权后令牌会缓存到指定路径，后续运行无需重复授权。

内容的提问来源于stack exchange，提问作者Adam Zbudniewek