public static string StringToTableKey()

in code/Utils/ExtensionMethods.cs [25:69]
37 lines of code
6 McCabe index (conditional complexity)

        public static string StringToTableKey(this string rowKeyString)
        {
            // check string is not null
            if (string.IsNullOrEmpty(rowKeyString))
            {
                throw new ArgumentNullException("rowKeyString");
            }

            // Replace characters that are not allowed (see https://msdn.microsoft.com/library/azure/dd179338.aspx ).
            // Note that the list on MSDN is incomplete. For example, + is not allowed
            Regex disallowedCharsInTableKeys = new Regex(@"[\\#%+/?\u0000-\u001F\u007F-\u009F]");
            StringBuilder safeRowKeyString = new StringBuilder();
            foreach (char c in rowKeyString)
            {
                // replace only the disallowed characters with encoded versions
                if (disallowedCharsInTableKeys.IsMatch(c.ToString()))
                {
                    byte[] bytes = Encoding.UTF8.GetBytes(new char[] { c });
                    string convertedString = Convert.ToBase64String(bytes);

                    // base64 strings can have '/' which is not allowed in Azure Table keys
                    convertedString = convertedString.Replace('/', '_');
                    safeRowKeyString.Append(convertedString);
                }
                else
                {
                    // preserve some human readability by keeping safe characters as is
                    safeRowKeyString.Append(c);
                }
            }

            // key can be up to 1KB in size
            if (safeRowKeyString.Length > 1024)
            {
                throw new ArgumentException("Azure Table keys can be up to 1 KB in length", "rowKeyString");
            }

            // key has to be at least 1 char long
            if (safeRowKeyString.Length < 1)
            {
                throw new ArgumentException("Azure Table keys have to be at least 1 char long", "rowKeyString");
            }

            return safeRowKeyString.ToString();
        }