using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"(?<!\d)(?!000|666|9)(order\W?number)?\W*(?<!x)\d{3}[ .=-]{0,10}(?!000)\d{3}[ .=-]{0,10}(?!000)\d{3}";
string input = @"x123456789
X123456789
x123-456-789
X123-456-789
123-456-789
ordernumber123-456-789
order number123-456789
order number 123456789
123-456789
123456789
ordernumber-123456787
ordernumber - 123456789
ordernumber #123456789
ordernumber !@#$%^&123456789
";
RegexOptions options = RegexOptions.IgnoreCase | 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