How to cause XmlSerializer to generate attributes instead of elements by default

Is there a way to cause XmlSerializer to serialize primitive class members (e.g. string properties) as XML attributes, not as XML elements, without having to write [XmlAttribute] in front of each property declaration? I.e. is there a global switch that tells XmlSerializer to serialize all primitive class members as XML attributes?

Assume that we have the following class:

public class Person
{
    public string FirstName
    {
       ...
    }

    public string LastName
    {
       ...
    }
}

Then XmlSerializer generates this code by default:

<Person>
    <FirstName>John</FirstName>
    <LastName>Doe</LastName>
</Person>

What I want, however, is this code:

<Person FirstName="John" LastName="Doe"/>

Again: I want to do that without [XmlAttribute] (or without XmlAttributeOverrides, which would be even more work).

One possible solution would be to use a generic postprocessing step that applies an XSLT transform to convert elements to attributes. But I wonder whether there is a simpler solution.