PayPal API，HttpWebRequest抛出SSL WebException
我正在尝试获取PayPal访问令牌，如下所示： https ： //developer.paypal.com/docs/integration/direct/make-your-first-call/#get-an-access-token
我的C＃代码如下所示：
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://api.sandbox.paypal.com/v1/oauth2/token"); request.Headers["Authorization"] = "Basic " + Convert.ToBase64String(Encoding.Default.GetBytes(clientId + ":" + clientSecret)); request.Accept = "application/json"; request.Headers.Add("Accept-Language", "en_US"); request.Method = "POST"; request.ContentType = "application/x-www-form-urlencoded"; request.Timeout = 10000; byte[] postBytes = Encoding.ASCII.GetBytes("grant_type=client_credentials"); request.ContentLength = postBytes.Length; ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3; ServicePointManager.ServerCertificateValidationCallback = delegate { return true; }; Stream postStream = request.GetRequestStream(); // ###### Here I get the Exception! ###### postStream.Write(postBytes, 0, postBytes.Length); postStream.Flush(); postStream.Close(); HttpWebResponse response = (HttpWebResponse)request.GetResponse(); 当调用request.GetRequestStream（）时，我得到一个带有德语文本的WebException“Die Anfrage wurde abgebrochen：Es konntekeingeschützterSSL/ TLS-Kanal erstellt werden。” 这意味着它无法创建安全的SSL / TLS通道。
我做错了什么？ 有谁能够帮我？
谢谢，Volker
我找到了解决方案：
ServicePointManager.SecurityProtocol = (SecurityProtocolType)3072; //SecurityProtocolType.Tls12;
也许它也有助于其他人……
正确他们不再使用SSL 3，这是错误的来源。
您可以使用TLS 1.1和1.2
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;