using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"^(\()?0?\d{2}(?(1)\) |[ -])\d{4,5}[ -]?\d{4}$";
string input = @"00 00000000
000-000000000
000 00000-0000
00 0000-0000
(00) 0000-0000
(000) 000000000
(00( 0000-0000
00) 0000-0000";
RegexOptions options = RegexOptions.Multiline;
foreach (Match m in Regex.Matches(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