static string Make(string prefix, Collection<string> fields)
{
if (fields == null || fields.Count == 0)
{
return prefix;
}
StringBuilder sb = new StringBuilder();
sb.Append(prefix);
sb.Append('=');
sb.Append('"');
sb.Append(string.Join(", ", fields.ToArray()));
sb.Append('"');
return sb.ToString();
}
}