using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"^([01][0-9][0-9]\.|2[0-4][0-9]\.|[0-9][0-9]\.|25[0-5]\.|[0-9]\.)([01][0-9][0-9]\.|2[0-4][0-9]\.|[0-9][0-9]\.|25[0-5]\.|[0-9]\.)([01][0-9][0-9]\.|2[0-4][0-9]\.|[0-9][0-9]\.|25[0-5]\.|[0-9]\.)([01][0-9][0-9]|2[0-4][0-9]|25[0-5]|[0-9][0-9]|[0-9])$";
string input = @"0.0.0.0
1.1.1.1
101.101.101.101
255.255.255.255
";
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