How to provide ILogger<ClassName> instance in new class object from controller in .net core?

user_13439648 0
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As giving null it gives Value cannot be null. (Parameter 'logger') error. Even if instance of model is given it still stays null

 public class MyController : Controller
    {
            public MyController(ILogger<MyController> logger)
            {
              logger.LogInformation("Log Testing");
            }

            public ActionResult List()
            {
                int Id = 5;
                MyModel model = new MyModel(null);
                model.GetItem(Id);
                return View("List", model);
            }
    }

public class MyModal:BaseModel
{
    private readonly ILogger<MyModal> _logger;
    public MyModel(ILogger<MyModel> logger) 
        {
           this._logger = logger;
        }

    public MyModel GetItem (Int Id)
    {
      try
      {
        //My Code
      }
      catch(Exception e){
       _logger.LogError(e.Message);
      }
    }
}

As per the suggestion i edited my question

ilogger asp.net-core logging .net c#
1 Answers

As suggested in the comments:

  1. Inject ILoggerFactory into MyController and store it in a field variable (e.g. _loggerFactory).
  2. Use the factory to construct a logger for MyModel in your List method: ILogger<MyModel> modelLogger = _loggerFactory.CreateLogger<MyModel>();
  3. Pass it into the MyModel constructor: MyModel model = new MyModel(modelLogger);

Example:

public class MyController
{
    private readonly ILogger _logger;
    private readonly ILoggerFactory _loggerFactory;
    
    public MyController(ILogger<MyController> logger, ILoggerFactory loggerFactory)
    {
        _logger = logger;
        _loggerFactory = loggerFactory;
    }

    public ActionResult List()
    {
        int Id = 5;
        ILogger<MyModel> modelLogger = _loggerFactory.CreateLogger<MyModel>();
        MyModel model = new MyModel(modelLogger);
        model.GetItem(Id);
        return View("List", model);
    }
}

Try it online

user_31819330
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