RegexParser.Patterns.CharPattern.IsMatch C# (CSharp) Method

        public abstract bool IsMatch(char c);

 public override bool IsMatch(char c)
 {
     if (char.IsLetter(c))
     {
         return(ChildPattern.IsMatch(char.ToLower(c)) ||
                ChildPattern.IsMatch(char.ToUpper(c)));
     }
     else
     {
         return(ChildPattern.IsMatch(c));
     }
 }