/// <summary>
/// Ises the quantifier.
/// </summary>
/// <returns>
/// The quantifier.
/// </returns>
/// <param name='_value'>
/// If set to <c>true</c> _value.
/// </param>
public static bool isQuantifier(System.Char _value)
{
string pattern = @"[\+\.\*\?]";
Regex rgx = new Regex(pattern);
return(rgx.IsMatch(_value.ToString()));
}