How to Make Flash Characters go up Inclines/Hills?

Hi, so I’m new to these forums, and to ActionScript, and I’m creating a Flash platformer-shooter. It’s all going well so far and I’ve found some great tutorials and threads showing how to code particular things in ActionScript 3, but there’s one thing that no matter what I do, I just can’t fix, and that’s getting the character to walk up uneven and hilly surfaces.

At the moment all that happens is the character hits an incline and just stops as if it’s a wall, and I have to repeatedly jump to get up the incline, which isn’t very practical. I’ve searched all over for ways to fix it but still have found nothing. Does anyone have advice for fixing this? Might take some explaining as I’m a beginner at this, but any help would be appreciated!