using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"CA_[A-Z][0-9][A-Z]\h?[0-9][A-Z][0-9]|US_[0-9]{5}|GB_(?:(?:[A-Z][0-9]|[A-Z][0-9]{2}|[A-Z]{2}[0-9]|[A-Z]{2}[0-9]{2}|[A-Z][0-9][A-Z]|[A-Z]{2}[0-9][A-Z])\h?[0-9][A-Z]{2}|GIR\h?0AA)";
string input = @"CA_LSE2B9";
Match m = Regex.Match(input, pattern);
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