在 asp.net core 2.2 中找不到类型或命名空间名称“Worker”（您是否缺少 using 指令或程序集引用？）？

Question

I have asp.net core 2.2 project in which i have created a service named Worker.cs which looks like this

 using System; using System.Linq; using System.Threading; using System.Threading.Tasks; using Amazon.SQS; using Amazon.SQS.Model; using Microsoft.Extensions.Hosting; using Microsoft.Extensions.Logging; using Newtonsoft.Json; namespace sqs_processor { public class Worker : BackgroundService { private readonly ILogger<Worker> _logger; private readonly IAmazonSQS _sqs; private readonly string _exampleQueueUrl = "https://sqs.ap-southeast-2.amazonaws.com/637294848563/example-queue"; private readonly string _processedMessageQueueUrl = "https://sqs.ap-southeast-2.amazonaws.com/637294848563/processed-messages"; public Worker(ILogger<Worker> logger, IAmazonSQS sqs) { _logger = logger; _sqs = sqs; } protected override async Task ExecuteAsync(CancellationToken stoppingToken) { while (!stoppingToken.IsCancellationRequested) { try { var request = new ReceiveMessageRequest { QueueUrl = _exampleQueueUrl, MaxNumberOfMessages = 10, WaitTimeSeconds = 5 }; var result = await _sqs.ReceiveMessageAsync(request); if (result.Messages.Any()) { foreach (var message in result.Messages) { // Some Processing code would live here _logger.LogInformation("Processing Message: {message} | {time}", message.Body, DateTimeOffset.Now); var processedMessage = new ProcessedMessage(message.Body); var sendRequest = new SendMessageRequest(_processedMessageQueueUrl, JsonConvert.SerializeObject(processedMessage)); var sendResult = await _sqs.SendMessageAsync(sendRequest, stoppingToken); if (sendResult.HttpStatusCode == System.Net.HttpStatusCode.OK) { var deleteResult = await _sqs.DeleteMessageAsync(_exampleQueueUrl, message.ReceiptHandle); } } } } catch (Exception e) { _logger.LogError(e.InnerException.ToString()); } _logger.LogInformation("Worker running at: {time}", DateTimeOffset.Now); } } } public class ProcessedMessage { public ProcessedMessage(string message, bool hasErrors = false) { TimeStamp = DateTime.UtcNow; Message = message; HasErrors = hasErrors; } public DateTime TimeStamp { get; set; } public string Message { get; set; } public bool HasErrors { get; set; } } }

Now when i am adding this service in my Startup.cs like this

public void ConfigureServices(IServiceCollection services)
    {
        services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
        services.AddCors(c =>
        {
            c.AddPolicy("AllowOrigin", options =>
            {
                options.AllowAnyOrigin();
            });
        });


         // AWS Configuration
                var awsoptions = Configuration.GetAWSOptions();
                services.AddDefaultAWSOptions(awsoptions);
                services.AddAWSService<IAmazonSQS>();

                // Worker Service
                services.AddHostedService<Worker>();
    }

So on registering Worker.cs in my Startup.cs it throws an error like this

Startup.cs(46,47): error CS0246: The type or namespace name 'Worker' could not be found (are you missing a using directive or an assembly reference?) [D:\OfficeProjects\beelinksanalytics\analytics.csproj]

So what i am doing wrong in this? I just simple want to add that Worker.cs in my Startup.cs . But curreny it is throwing an error.

Answer 1

You need to add the namespace of your Worker class on the usings of your startup class.

in your case it should be like this:

using sqs_processor;

When you get this kind of error, you can make visual studio resolve it put your cursor on the class name and pressing Ctrl + . then Visual Studio will give you some options to solve it.