YamlDotNet.Core.Scanner.ScanTagHandle C# (CSharp) Method

        private string ScanTagHandle(bool isDirective, Mark start)
        {
            // Check the initial '!' character.

            if (!analyzer.Check('!'))
            {
                throw new SyntaxErrorException(start, cursor.Mark(), "While scanning a tag, did not find expected '!'.");
            }

            // Copy the '!' character.

            var tagHandle = new StringBuilder();
            tagHandle.Append(ReadCurrentCharacter());

            // Copy all subsequent alphabetical and numerical characters.

            while (analyzer.IsAlphaNumericDashOrUnderscore())
            {
                tagHandle.Append(ReadCurrentCharacter());
            }

            // Check if the trailing character is '!' and copy it.

            if (analyzer.Check('!'))
            {
                tagHandle.Append(ReadCurrentCharacter());
            }
            else
            {

                // It's either the '!' tag or not really a tag handle.  If it's a %TAG
                // directive, it's an error.  If it's a tag token, it must be a part of
                // URI.

                if (isDirective && (tagHandle.Length != 1 || tagHandle[0] != '!'))
                {
                    throw new SyntaxErrorException(start, cursor.Mark(), "While parsing a tag directive, did not find expected '!'.");
                }
            }

            return tagHandle.ToString();
        }