Command to collapse all sections of code?

CTRL + M + L expands all

CTRL + M + O collapses all

In the MSDN article "Default Keyboard Shortcuts in Visual Studio," see the section "Text Editor" if you're looking for other shortcuts - these 2 are just a few of the many that are available.

CTRL + M + O will collapse all.

CTRL + M + L will expand all. (in VS 2013 - Toggle All outlining)

CTRL + M + P will expand all and disable outlining.

CTRL + M + M will collapse/expand the current section.

CTRL + M + A will collapse all even in Html files.

These controls are also in the context menu under Outlining.

Right click in editor -> Outlining to find these controls. (After disabling outlining, use same steps to enable outlining.)

For outlining options: Go to Tools -> Options -> Text Editor -> C# -> Advanced -> Outlining for outlining options.

The following key combinations are used to do things:

CTRL + M + M → Collapse / Expand current preset area (e.g. Method)

CTRL + M + H → Collapse / Hide (Expand) current selection

CTRL + M + O → Collapse all(Collapse declaration bodies)

CTRL + M + A → Collapse all

CTRL + M + X → Expand all

CTRL + M + L → Toggle all

There some options in the context menu under Outlining.