如何创建 Google BaseClientService.Initializer 的实例

Google.Apis.Services.BaseClientService.Initializer initializer = new BaseClientService.Initializer();
initializer.ApiKey = "MyApiKey";
initializer.ApplicationName = "MyProject";
initializer.DefaultExponentialBackOffPolicy = Google.Apis.Http.ExponentialBackOffPolicy.None;
Google.Apis.Gmail.v1.GmailService gmailService = new GmailService(initializer);      
Google.Apis.Gmail.v1.UsersResource usersResource = new UsersResource(gmailService);
UsersResource.MessagesResource messagesResource = usersResource.Messages;

首先转到下面的链接，然后在您的Google帐户中打开一个应用程序。运行代码后，您将第一次收到异常，为您提供一个地址，并在您的Google帐户中启用API。

https://console.developers.google.com/apis/dashboard?project=super-pharm-log-notifications

      static string[] Scopes = { GmailService.Scope.GmailCompose, GmailService.Scope.GmailSend, GmailService.Scope.GmailInsert };
            static private BaseClientService.Initializer initializeGmailAccountServices()
            {
                string appRoot = null;

                    if (System.Web.HttpContext.Current == null)
                    {
                        appRoot = Environment.CurrentDirectory;
                    }
                    else
                    {
                        appRoot = System.Web.HttpContext.Current.Server.MapPath(@"~'");
                    }
                    string path = Path.Combine(appRoot, DBConstants.GMAIL_CREDENTIALS_PATH);

                    UserCredential credential;
                    using (var stream = new FileStream(path, FileMode.Open, FileAccess.Read))
                    {
                        ClientSecrets secrets = GoogleClientSecrets.Load(stream).Secrets;
                        var t =  GoogleWebAuthorizationBroker.AuthorizeAsync(secrets, Scopes, "user", CancellationToken.None);
                        t.Wait();
                        credential = t.Result;
                    }
                    return= new BaseClientService.Initializer()
                    {
                        HttpClientInitializer = credential,
                        ApplicationName = "your application name",
                    };
            }
private static string Base64UrlEncode(string input)
            {
                var inputBytes = System.Text.Encoding.UTF8.GetBytes(input);
                // Special "url-safe" base64 encode.
                return Convert.ToBase64String(inputBytes)
                  .Replace('+', '-')
                  .Replace('/', '_')
                  .Replace("=", "");
            }