Amazon.IdentityManagement.AmazonIdentityManagementServiceClient.AttachUserPolicyAsync C# (CSharp) Method

        public void AttachUserPolicyAsync(AttachUserPolicyRequest request, AmazonServiceCallback<AttachUserPolicyRequest, AttachUserPolicyResponse> callback, AsyncOptions options = null)
        {
            options = options == null?new AsyncOptions():options;
            var marshaller = new AttachUserPolicyRequestMarshaller();
            var unmarshaller = AttachUserPolicyResponseUnmarshaller.Instance;
            Action<AmazonWebServiceRequest, AmazonWebServiceResponse, Exception, AsyncOptions> callbackHelper = null;
            if(callback !=null )
                callbackHelper = (AmazonWebServiceRequest req, AmazonWebServiceResponse res, Exception ex, AsyncOptions ao) => { 
                    AmazonServiceResult<AttachUserPolicyRequest,AttachUserPolicyResponse> responseObject 
                            = new AmazonServiceResult<AttachUserPolicyRequest,AttachUserPolicyResponse>((AttachUserPolicyRequest)req, (AttachUserPolicyResponse)res, ex , ao.State);    
                        callback(responseObject); 
                };
            BeginInvoke<AttachUserPolicyRequest>(request, marshaller, unmarshaller, options, callbackHelper);
        }