Tool C# Regular Expression

MasterGH

string allText = richTextBox1.Text;
string pattern = textBox2.Text;
string s = string.Empty;

try 
{
  Regex regex = new Regex(pattern);
  MatchCollection matches = regex.Matches(allText);			
  if (matches.Count > 0)
  {
      foreach (Match match in matches)
          s += match.Value + ";\r\n";
  }
  else
  {
      s = "Совпадений не найдено";
  }				
  textBox3.Text = s;
} catch (Exception) {
  
  //throw;
}