using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"^[A-Za-z0-9\u0430-\u044F\u0410-\u042F\._-]+@([A-Za-z0-9\u0430-\u044F\u0410-\u042F]{1,2}|[A-Za-z0-9\u0430-\u044F\u0410-\u042F]((?!(\.\.))[A-Za-z0-9\u0430-\u044F\u0410-\u042F.-])+[A-Za-z0-9\u0430-\u044F\u0410-\u042F])\.[A-Za-z\u0430-\u044F\u0410-\u042F]{2,}$";
string input = @"дсацс@абсд.бг";
RegexOptions options = RegexOptions.IgnoreCase;
Match m = Regex.Match(input, pattern, options);
Console.WriteLine("'{0}' found at index {1}", m.Value, m.Index);
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx