public async Task <OperationDetails> StopEC2InstancesByInstanceIds(List <string> instanceIds) { OperationDetails operationDetails = new OperationDetails(); try { using (AmazonEC2Client ec2Client = new AmazonEC2Client()) { StopInstancesRequest stopRequest = new StopInstancesRequest(instanceIds); StopInstancesResponse stopResponse = await ec2Client.StopInstancesAsync(stopRequest); operationDetails.StatusMessage = stopResponse != null?stopResponse.HttpStatusCode.ToString() : "null response"; } } catch (Exception ex) { operationDetails.StatusMessage = ex.Message; } return(operationDetails); }