Windsor dependency extension for connection strings

DependencyEx.cs

    public static class DependencyEx
    {
        public static Parameter OnConnectionString(string connectionStringName)
        {
            return OnConnectionString("connectionString", connectionStringName);
        }

        public static Parameter OnConnectionString(string dependencyName, string connectionStringName)
        {
            if (string.IsNullOrWhiteSpace(connectionStringName))
            {
                throw new ArgumentNullException("connectionStringName", "\"connectionStringName\" cannot be null or empty");
            }

            var connectionStringSetting = ConfigurationManager.ConnectionStrings[connectionStringName];
            if (connectionStringSetting == null)
            {
                throw new ConfigurationErrorsException(
                    $"Could not find a connection string named \"{connectionStringName}\" in the <connectionStrings> section of the config file");
            }

            var connectionString = connectionStringSetting.ConnectionString;
            return Parameter.ForKey(dependencyName).Eq(connectionString);
        }
    }