using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"(?!(\S*s){4}|(\S*t){2}|(\S*a){2}|(\S*i){2}|(\S*n){2}|(\S*l){2}|(\S*e){2})\b[stainless]+\b";
string input = @"Found Words : stainless, stain, net, ten, less, sail, sale, tale, tales, ants
Unacceptable words to find : tent, tall
Acceptable words to find : less
";
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