Force 2D snapping when on ortho view

 From:  Samuel Zeller
Hi guys,

A quick question here. I'm often re-drawing curves from CAD files from left/right or top/down views.

So I often create a new style and start making 2D curves and lines on top of existing geometry.

Is there a shortcut to toggle between 2D snap and 3D snap ?

So when I finish my 2D drawing the points are all in the same plane :)