System.Net.HttpListenerRequest.GetClientCertificateAsync C# (CSharp) Method

        public Task<X509Certificate2> GetClientCertificateAsync()
        {
            throw new PlatformNotSupportedException();
        }

 /// <summary>
 /// Retrieves the client's X.509 v.3 certificate as an asynchronous operation.
 /// </summary>
 /// <returns></returns>
 public Task <X509Certificate2> GetClientCertificateAsync() => _request.GetClientCertificateAsync();