# Add new field to biblatex entries

Many of the books I use are parts of series. biblatex gives you more fields to add bibliographic information to than BibTeX does, but it has no fields appropriate for the editor of a series. If I use the EDITOR field, the bibliography will (by default) print edited by, which doesn't give the right impression of what the role of the series editor is.

I'm wondering if there is any easy way to add a new field SERIESEDITOR, which will make biblatex by default print its content preceded by Series edited by or make sure that whatever is in SERIESEDITOR gets printed directly after the name of the series, such that is says something like [Name of series], edited by [series editor]. In other words, is there any way I can do this in the preamble of my document, without having to venture into writing new bibliography styles?

-

biblatex 2.0+ and biber 1.0+ allow you to define additional fields and entry types, but this is intended for style authors and can't be used in the document preamble.

With biber's source map feature you can however use the field serieseditor and map it to a field defined in the default data model, such as namea. This existing field can then be printed in the bibliography macro that sets the series field.

\DeclareSourcemap{
\maps[datatype=bibtex]{
\map{
\step[fieldsource=serieseditor,fieldtarget=namea]
}
}
}

\renewbibmacro*{series+number}{%
\printfield{series}%
\printfield{number}%
\ifnameundef{namea}
{}

Since version 2 (and in combination with biber, version 1 or greater) biblatex allows you define any kind of additional field. Check out chapter 4.5.2 of the biblatex manual.
I did look there, but I didn't, and don't, understand what I need to do to make biblatex parse a field I've added to my entries. –  Sverre Jul 31 '12 at 19:01
To have biblatex parse it you must of course adapt the style files. For example, if you add a field serieseditor, you must look which parts of the .bbx/.cbx should handle this field and write the needed adaptation. –  Simifilm Jul 31 '12 at 19:26