C# 请求被中止: 未能创建 SSL/TLS 安全通道”的原因及解决办法 代码前加上如下代码: ServicePointManager.Expect100Continue = true; ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls; ServicePointMa