using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"^(([\d]{5})-([\d]{7})-([\d]{1}))|(([\d]{5})([\d]{7})([\d]{1}))|(([\d]{5}) ([\d]{7}) ([\d]{1}))$";
string input = @"// Allow these:
1234512345671
12345-1234567-1
// Don't Allow
12345 1234567-1
12345-1234567 1
12345123456718
12345-1234567-71
12345-12345678-1
";
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