Queries :: Conditionally Choose Fields In SELECT Clause

I have a table with 2 fields:

CODEDATE (text)
DATE1 (date)(dd/mm/yyyy)

RECORDS SAMPLE:

Code:
-------------------------------------
CODEDATE DATE1
-------------------------------------
TT-10/10/2013 01/01/2012
ASDFDFDF 01/02/2013
RR-18/06/2012 05/08/2012
------------------------------------

I need to extract the date from CODEDATE field if the "-" character exist in or from DATE1 if the character "-" is not present in the CODEDATE field, then filter the query on the date found.

I wrote that:

Code:
SELECT IIf(Mid([CODEDATE],3,1)='-',Mid([CODEDATE],4,10),[DATE1]) AS DateFound
FROM MyTable
WHERE (IIf(Mid([CODEDATE],3,1)='-',Mid([CODEDATE],4,10),[DATE1])
Between 1/1/2013 And 31/12/2013)

The query above extra extract some records without sense for me, I tried many other syntax without success.