Layer
Using layers organizes objects so you can manipulate them all at once or keep track of them. When objects have a layer assignment, you can turn them all off at once, change their wireframe display color, and select them all with one selection.
Manage layer properties.
Save and restore the current layer state.
Turn off an object's layer.
Turn a layer on and all other layers off.
Delete unused block definitions, groups, layers, hatch patterns, linetypes, dimension styles, and materials.
Set the current layer to match a specified object.
Change an object's layer.
Change an object's layer to the current layer.
Copy objects to a layer.
Change an object's layer to match another object.
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