.net取域名

using Microsoft.AspNetCore.Http;
using System;

public class DomainHelper
{
    public static string GetCurrentDomainName(HttpContext context)
    {
        if (context == null)
        {
            throw new ArgumentNullException(nameof(context));
        }

        return $"{context.Request.Scheme}://{context.Request.Host}";
    }
}

using System;
using System.Net;

public class DnsHelper
{
    public static IPAddress GetHostAddress(string hostName)
    {
        if (string.IsNullOrEmpty(hostName))
        {
            throw new ArgumentException("Host name cannot be null or empty", nameof(hostName));
        }

        return Dns.GetHostAddresses(hostName).FirstOrDefault();
    }
}