using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"^(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\/((((([0-9])|(?:[1-2][0-9])|(?:3[0-2]))|(([1-9]?\\d|1\\d\\d|25[0-5]|2[0-4]\\d)\.){3}([1-9]?\\d|1\\d\\d|25[0-5]|2[0-4]\\d)(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])))|(((255\.){3}(255|254|252|248|240|224|192|128|0+))|((255\.){2}(255|254|252|248|240|224|192|128|0+)\.0)|((255\.)(255|254|252|248|240|224|192|128|0+)(\.0+){2})|((255|254|252|248|240|224|192|128|0+)(\.0+){3})))$";
string input = @"0.0.0.0/32
10.10.10.10/32
10.10.10.10/255.255.255.255
99.99.99.99
100.100.100.100
199.199.199.199
200.200.200.200
255.255.255.255
255.255.255.255/24
256.256.256.256
1.1.1.1.1";
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