c# - 如何将 ILogger<T> 依赖项注入(inject) ConfigureServices - .net core 2.0 中的服务

Question

我有以下 MailService:

public class MailService : IMailService
{
    private readonly ILogger<MailService> _logger;
    private readonly SmtpClient _client;

    public MailService(ILogger<MailService> logger, SmtpClient client)
    {
        _logger = logger;
        _client = client;
    }

    public async Task Send(string to, string subject, string body)
    {
        var message = new MailMessage
        {
            Subject = subject,
            Body = body,
            IsBodyHtml = true,
            From = new MailAddress("info@domain.com")
        };

        message.To.Add(to);

        using (_client)
        {
            _logger.LogTrace($"Sending email from {message.From.Address} to {to}. Subject: {subject}");
            await _client.SendMailAsync(message);
        }
    }

}

我想使用实现工厂创建此服务，因为我将从配置中读取 smtp 设置并在 Startup.cs 中提供 smtp 客户端，如下所示:

services.AddTransient<IMailService>(provider =>
{
    var mailService = new MailService(***LOGGER INSTANCE HERE***, new SmtpClient("127.0.0.1", 25));
    return mailService;
});

有没有办法获取记录器实例并将其提供给邮件服务？

Answer 1

这行不通吗？

services.AddTransient<IMailService>(provider =>

        {
            return new MailService(provider.GetRequiredService<ILogger<MailService>>(), new SmtpClient());
        });