How to prevent wilted string beans?

Hey, I want my string beans to be tasty with sauteed garlic and onions, but when I reheat them they wilt. How do I prevent this???
Should I only blanch them for a short amount of time and then reheat them when I need them?
I have this problem often and the string beans look awful and don't have the right kick to them when wilted.
Your advice is nice... so help me please!

not much you can do to prevent that. Try to steam them instead of immersing them in water. The texture is better that way.