Well you cannot not, you need more infomation than that.

each tile needs to know its filename, not its DC (which changes)

have a look on how i did mine (the bit that is missing is the code to save the contents of SurfaceCollection, but it will work exactly the same as the code that saves the map.

if your willing to partly use DirectX, adding a single property to SurfaceCollectionItem - getDC will make it work with the gdi