Visual Studio – Expand and Collapse Regions

CTRL+M CTRL+M (that’s two key presses!) – collapse/open the current parent region

CTRL+M CTRL+L – Collapse/Open all regions in document recursively (meaning you might get only one line in the document – one big namespace region which is collapsed or you’ll see the entire page code uncollapsed

CTRL+M CTRL+O – Collapse all regions not recursively

Courtesy :–expand-all-regions-and-rockscroll.aspx