using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"(?<![-\.\d])(?:0{0,2}?[0-9]\.|1\d?\d?\.|2[0-5]?[0-5]?\.){3}(?:0{0,2}?[0-9]|1\d?\d?|2[0-5]?[0-5]?)(?![\.\d])";
string input = @"str1 = 'Hello my name is Ben and my IP address is 256.0.0.0'
negative number is invalid: -127.2.1.2
valid: 001.001.001.001
str2 = 'Hello my name is Folks and my IP address is 1.2.3.4.5'
str3 = 'Hello all, ip addresses: 111.2.3., ip:0.0.0.0, 127.2.1.2'";
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