I would like to implement singleton pattern in StudentProvider and then access method through interface. StudentProvider constructor accepts few parameters. Here's the sample working code without singleton.
public interface IStudentProvider
{
Task<StudentViewModel> GetStudentAsync();
}
public class StudentProvider : IStudentProvider
{
private readonly HttpContext httpContext;
private readonly IActionContextAccessor actionContextAccessor;
private readonly IConfiguration configuration;
private readonly IUnitOfWork unitOfWork;
private readonly string host;
public StudentProvider(IHttpContextAccessor _httpContextAccessor, IActionContextAccessor _actionContextAccessor, IConfiguration _configuration, IUnitOfWork _unitOfWork)
{
httpContext = _httpContextAccessor.HttpContext;
actionContextAccessor = _actionContextAccessor;
configuration = _configuration;
unitOfWork = _unitOfWork;
host = _httpContextAccessor.HttpContext.Request.Host.Host;
}
public async Task<StudentViewModel> GetStudentAsync()
{
var std = new StudentViewModel();
// httpContext, actionContextAccessor, configuration, unitOfWork and host uses here
return std;
}
}
Now i converted this into single, here's the code:
public interface IStudentProvider
{
Task<StudentViewModel> GetStudentAsync();
}
public sealed class StudentProvider : IStudentProvider
{
private readonly HttpContext httpContext;
private readonly IActionContextAccessor actionContextAccessor;
private readonly IConfiguration configuration;
private readonly IUnitOfWork unitOfWork;
private readonly string host;
private static StudentProvider instance = null;
public static StudentProvider GetInstance
{
get
{
if (instance == null)
{
instance = new StudentProvider();
}
return instance;
}
}
private StudentProvider(IHttpContextAccessor _httpContextAccessor, IActionContextAccessor _actionContextAccessor, IConfiguration _configuration, IUnitOfWork _unitOfWork)
{
httpContext = _httpContextAccessor.HttpContext;
actionContextAccessor = _actionContextAccessor;
configuration = _configuration;
unitOfWork = _unitOfWork;
host = _httpContextAccessor.HttpContext.Request.Host.Host;
}
public async Task<StudentViewModel> GetStudentAsync()
{
var std = new StudentViewModel();
// httpContext, actionContextAccessor, configuration, unitOfWork and host uses here
return std;
}
}
The issue with above singleton code is instance = new StudentProvider();
is expecting parameters which i'm not able to pass.
How do i pass parameters to constructor from singleton instance ?
Aucun commentaire:
Enregistrer un commentaire