public override bool TryInvokeMember(
    InvokeMemberBinder binder,
    object[] args,
    out object result)
{
    string arg = GetValue(args);
    string methodName = binder.Name;

    if (methodName == "Tag" && arg != null)
    {
        result = ToString().Tag(arg);
    }
    else
    {
        _props[methodName] = arg ?? string.Empty;
        result = this;
    }

    return true;
}