在C#中使用OAuth2通过Google API进行身份验证

using Google.Apis.Auth.OAuth2;
using Google.Apis.Services;
using Google.Apis.Util.Store;
using Google.Apis.Auth.OAuth2.Flows;
using Google.Apis.Auth.OAuth2.Responses;

// ...

UserCredential credential;
using (var stream = new FileStream("client_secret.json", FileMode.Open, FileAccess.Read))
{
    credential = await GoogleWebAuthorizationBroker.AuthorizeAsync(
        GoogleClientSecrets.Load(stream).Secrets,
        new[] { "https://www.googleapis.com/auth/userinfo.email" },
        "user",
        CancellationToken.None,
        new FileDataStore("token.json"));
}

// 创建一个Google API服务
var service = new Google.Apis.Oauth2.v2.Oauth2Service(new BaseClientService.Initializer()
{
    HttpClientInitializer = credential,
    ApplicationName = "Your Application Name",
});

// 获取用户信息
var userInfo = await service.Userinfo.Get().ExecuteAsync();
Console.WriteLine("User ID: " + userInfo.Id);
Console.WriteLine("Email: " + userInfo.Email);