# Commands about Underlays [GstarCAD 2027](Help%20System/GSTARCAD/2027/Index.md) → [Commands](Help%20System/GSTARCAD/2027/Commands/(Commands).md) → [Command Groups](Help%20System/GSTARCAD/2027/Commands/00%20Command%20Groups/(Command%20Groups).md) **Commands：** - [ATTACH (GstarCAD 2026)](../../../2026/Commands/A/ATTACH.md) - [DGNADJUST (GstarCAD 2026)](../../../2026/Commands/D/DGNADJUST.md) - [DGNATTACH (GstarCAD 2026)](../../../2026/Commands/D/DGNATTACH.md) - [DGNCLIP (GstarCAD 2026)](../../../2026/Commands/D/DGNCLIP.md) - [DGNLAYERS (GstarCAD 2026)](../../../2026/Commands/D/DGNLAYERS.md) - [DWFATTACH (GstarCAD 2026)](../../../2026/Commands/D/DWFATTACH.md) - [DWFLAYERS (GstarCAD 2026)](../../../2026/Commands/D/DWFLAYERS.md) - [EXTERNALREFERENCES (GstarCAD 2026)](../../../2026/Commands/E/EXTERNALREFERENCES.md) - [IMAGEATTACH (GstarCAD 2026)](../../../2026/Commands/I/IMAGEATTACH.md) - [NCOPY (GstarCAD 2026)](../../../2026/Commands/N/NCOPY.md) - [PDFADJUST (GstarCAD 2026)](../../../2026/Commands/P/PDFADJUST.md) - [PDFATTACH (GstarCAD 2026)](../../../2026/Commands/P/PDFATTACH.md) - [PDFCLIP (GstarCAD 2026)](../../../2026/Commands/P/PDFCLIP.md) - [PDFLAYERS (GstarCAD 2026)](../../../2026/Commands/P/PDFLAYERS.md) - [PROPERTIES (GstarCAD 2026)](../../../2026/Commands/P/PROPERTIES.md) - [VPCLIP (GstarCAD 2026)](../../../2026/Commands/V/VPCLIP.md) **System Variables：** - [DGNFRAME (GstarCAD 2026)](Help%20System/GSTARCAD/2026/System%20Variables/D/DGNFRAME.md) - [DGNOSNAP (GstarCAD 2026)](Help%20System/GSTARCAD/2026/System%20Variables/D/DGNOSNAP.md) - [DWFFRAME (GstarCAD 2026)](Help%20System/GSTARCAD/2026/System%20Variables/D/DWFFRAME.md) - [DWFOSNAP (GstarCAD 2026)](Help%20System/GSTARCAD/2026/System%20Variables/D/DWFOSNAP.md) - [ERHIGHLIGHT (GstarCAD 2026)](Help%20System/GSTARCAD/2026/System%20Variables/E/ERHIGHLIGHT.md) - [PDFFRAME (GstarCAD 2026)](Help%20System/GSTARCAD/2026/System%20Variables/P/PDFFRAME.md) - [PDFOSNAP (GstarCAD 2026)](Help%20System/GSTARCAD/2026/System%20Variables/P/PDFOSNAP.md) - [UOSNAP (GstarCAD 2026)](Help%20System/GSTARCAD/2026/System%20Variables/U/UOSNAP.md) --- [Original help](https://www.gstarcad.net/help/GstarCAD_2027_en-US/detail/commandReferences/Commands%20about%20Underlays.html) · © Gstarsoft Co., Ltd.