How to extract e-mails from a text file with Regex (Regular expression)

EmailExtractor

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Text.RegularExpressions;

namespace Task_18_E_MailExtract
{
class MailExtractor
{
static void Main()
{
    StreamReader Input = new StreamReader(@"..\..\InputFile.txt");
    string InputContent = "";
    StringBuilder Output = new StringBuilder();
    string Pattern = @"\b[A-Z0-9._%+-]+@(?:[A-Z0-9-]+\.)+[A-Z]{2,4}\b";
    Regex mail = new Regex(Pattern,RegexOptions.IgnoreCase);

    using (Input)
    {
        InputContent = Input.ReadToEnd();   
    }

    MatchCollection MC = mail.Matches(InputContent);

    foreach (var match in MC)
    {
        Output.AppendLine(match.ToString());
    }

    Console.WriteLine(Output);
}
}
}