I know you can't search a container field directly..

But I have container fields which stores audit documents related to particular suppliers. these docs are Word, excel etc. Is there some way I can create a text field which automatically( by a calculation?) takes the file name of the document that has been imported into the container field? Then the text field would be searchable. How do I do this. Had a look through the other posts in the 'Containers' sub forum but couldn't see anything.

Try a calculation field (result is Text) =

Containerfield

If the file is physically stored in Containerfield, the result will be file's name.

If Containerfield keeps only a reference to the file, the result will be paths to the file (relative and absolute).

Thanks for this, as always these things seem a bit obvious when someone points it our for you. Much appreciated.

One final question: is there a way I can get a container field holding a document just to display the icon of the document, not the file name? Apart from setting the font size to 1pt?

I don't think you can control what a container field displays, only how it's displayed. I would set the font color to white (or to the field's fill color - if the field has a fill color).

Alternatively, you could cover the field with another field showing a custom icon ... but it seems like a lot of effort for a trivial task.