Resize box as mouse moves

Hey,

I’m making a quite basic selection box thing. You mouse down somewhere and then drag a box around an area.

Redrawing the rectangle on every mouse move update is quite heavy so I’m trying to set the height and width of an already drawn sprite.

But, I get a problem when I try to set the height and width of a rectangle that has boarders.
When I’m resizing a normal vector rectangle then everything happens as you would expect. But when I add the boarder box.graphics.lineStyle(1, 0xFF0000, 1, true, “none”); everything goes wrong. The box does resize but it goes way slower then my mouse.

Example: When my mouse is at 200x200 the box has a size of 100x100 and so on.

Is there something I’m missing? Or could it possibly be, that flash is scaling the boarder as it should, then making it a hairline again, but the width of the already scaled boarder still stays?