Testing email address validation, C#

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//Title of this code
//Rextester.Program.Main is the entry point for your code. Don't change it.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Globalization;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class Program
    {
        
        
        public static bool IsValidEmail(string strIn)
        {
			bool invalid = false;

if (String.IsNullOrEmpty(strIn))
                return false;

// Use IdnMapping class to convert Unicode domain names.
            strIn = System.Text.RegularExpressions.Regex.Replace(strIn, @"(@)(.+)$", DomainMapper);
            if (invalid)
                return false;

// Return true if strIn is in valid e-mail format.
            return System.Text.RegularExpressions.Regex.IsMatch(strIn,
                   @"^(?("")("".+?(?<!\\)""@)|(([0-9a-z]((\.(?!\.))|[-!#\$%&'\*\+/=\?\^`\{\}\|~\w])*)(?<=[0-9a-z])@))" +
                @"(?(\[)(\[(\d{1,3}\.){3}\d{1,3}\])|(([0-9a-z][-\w]*[0-9a-z]*\.)+[a-z0-9][\-a-z0-9]{0,22}[a-z0-9]))$",
                   System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        }
        
        private static string DomainMapper(Match match)
        {
            // IdnMapping class with default property values.
            IdnMapping idn = new IdnMapping();

string domainName = match.Groups[2].Value;
            try
            {
                domainName = idn.GetAscii(domainName);
            }
            catch (ArgumentException ex)
            {
                Console.WriteLine("Error occured:"+ex.Message);
            }
            catch(Exception ex2)
            {
                Console.WriteLine("Error occured:"+ex2.Message);
            }
            return match.Groups[1].Value + domainName;
        }
        public static void Main(string[] args)
        {
             
            
            Console.WriteLine(IsValidEmail("jorgelu00_@hotmail.com").ToString());
            
        }
    }
}

Show compiler warnings [ + ] Show input
Compilation time: 0.14 sec, absolute running time: 0.11 sec, cpu time: 0.09 sec, average memory usage: 16 Mb, average nr of threads: 4 (cached)