Use layers
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 layers
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Layer
Toggle Layer panel.
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LayerStateManager
Save and restore the current layer state.
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DupLayer
Duplicate (copy) a layer including all layer attributes and geometry.
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OneLayerOff
Turns off the selected object's layer.
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OneLayerOn
Turns a specified layer on and all other layers off.
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Purge
Delete unused block definitions, groups, layers, hatch patterns, linetypes, annotation styles, and materials.
Edit layer properties
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SetLayerToObject
Set the current layer to match a specified object.
Object layer properties
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ChangeLayer
Change an object's layer.
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ChangeToCurrentLayer
Change an object's layer to the current layer.
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CopyToLayer
Copy objects to a layer.
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MatchLayer
Change an object's layer to match another object.