使用OAuth在Sharepoint中创建列表项

Question

我想在C＃中使用Oauth身份验证在Sharepoint中创建一个新列表项。我已经通过我的Azure服务器登录了该应用程序并进行了所有配置，但是我陷入了C＃部分。我已经具有基本身份验证，如下所述。但是我需要将其更改为OAuth。

string url = $"{endpoint}_api/web/lists/GetByTitle('{listName}')/items";
Logger.Write($"Creating sharepoint request: {url}", _loggerComponentName, LoggingCategory.ApplicationMonitoring);
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.Method = "POST";
request.Accept = "application/json;odata=verbose";
request.Headers.Add("Authorization", "Bearer " + accessToken);
request.Credentials = AuthorizationHelper.GetSharePointCredentials();
request.Headers.Add("X-RequestDigest", FormDigestHelper.FormDigest);
request.ContentType = "application/json;odata=verbose";

有人知道我该怎么做吗？

预先感谢