public IList<SectionDefinition> GetSections()

//var voxelLayer = ... ;
//Must be on the QueuedTask.Run()

//At 2.x -
//var section = voxelLayer.GetSections().FirstOrDefault();
//var section2 = voxelLayer.GetSections().First(sec => sec.Id == my_section_id);

//Use the SelectedVariableProfile to get the sections currently in the TOC
//via its associated volume
var volume = voxelLayer.SelectedVariableProfile.Volume;

var section = volume.GetSections().FirstOrDefault();
var section2 = volume.GetSections().First(sec => sec.ID == my_section_id);

//var voxelLayer = ... ;
//Must be on the QueuedTask.Run()

if (voxelLayer.Visualization != VoxelVisualization.Surface)
    voxelLayer.SetVisualization(VoxelVisualization.Surface);
voxelLayer.SetSectionContainerExpanded(true);
voxelLayer.SetSectionContainerVisibility(true);

//At 2.x - var sections = voxelLayer.GetSections();

//Use the SelectedVariableProfile to get the sections currently in the TOC
//via its associated volume
var volume = voxelLayer.SelectedVariableProfile.Volume;
var sections = volume.GetSections();

//var voxelLayer = ... ;
//Must be on the QueuedTask.Run()

if (voxelLayer.Visualization != VoxelVisualization.Surface)
    voxelLayer.SetVisualization(VoxelVisualization.Surface);
voxelLayer.SetSectionContainerExpanded(true);
voxelLayer.SetSectionContainerVisibility(true);

//Use the SelectedVariableProfile to get the sections
//via its associated volume
var volume = voxelLayer.SelectedVariableProfile.Volume;

//At 2.x - foreach (var section in voxelLayer.GetSections())
foreach (var section in volume.GetSections())
{
    //set each normal to 45.0 orientation and tilt
    section.Normal = voxelLayer.GetNormal(45.0, 45.0);
    //apply the change
    //At 2.x - voxelLayer.UpdateSection(section);
    volume.UpdateSection(section);
}

//var voxelLayer = ... ;
//Must be on the QueuedTask.Run()

if (voxelLayer.Visualization != VoxelVisualization.Surface)
    voxelLayer.SetVisualization(VoxelVisualization.Surface);
voxelLayer.SetSectionContainerExpanded(true);
voxelLayer.SetSectionContainerVisibility(true);

//At 2.x - var sections = voxelLayer.GetSections().Where(s => !s.IsVisible);

//Use the SelectedVariableProfile to get the sections
//via its associated volume
var volume = voxelLayer.SelectedVariableProfile.Volume;
var sections = volume.GetSections().Where(s => !s.IsVisible);

//Make them all visible
foreach (var section in sections)
{
    section.IsVisible = true;
    //apply the change
    //At 2.x - voxelLayer.UpdateSection(section);
    volume.UpdateSection(section);
}