using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"O\s+(?P<O>\d+\.\d+\.\d+\.\d+.*(?:[\r\n]+[^\S\r\n]+.*)?)";
string input = @"Gateway of last resort is not set
10.0.1.0/8 is variably subnetted, 4 subnets, 2 masks
C 10.1.0.0/24 is directly connected, Ethernet1/0
L 10.1.0.1/32 is directly connected, Ethernet0/0
C 10.2.0.0/24 is directly connected, Ethernet0/1
L 19.18.2.1/32 is directly connected, Serial2/1
O 19.18.3.0/20 [110/128] via 19.18.2.2, 00:00:50, Serial1/1
[110/128] via 19.18.1.2, 00:00:50, Serial1/0
O 12.18.3.1/20 [110/128] via 19.18.2.2, 00:00:50, Serial1/1
[110/128] via 19.18.1.2, 00:00:50, Serial1/0
O 12.18.1.0/20 [110/128] via 19.18.2.2, 00:00:50, Serial0/1
[110/128] via 19.18.1.2, 00:00:50, Serial0/0";
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