Maybe you’re new to SSIS, like I am, or maybe you just need a little refresher on expressions in SSIS. I just ran across the SSIS Expressions Cheatsheet. This is a page on the PragmaticWorks website. It’s also available as a downloadable .pdf file. For me, anyway, it’s a great one-page reference. I’ve got it printed and pinned to my cube wall.
I learned about this resource from Dougbert.com