Import codes from a sub assembly Civil 3D
To import codes to a code set style
In Toolspace, on the Settings tab, expand the General collection, the Multipurpose Styles collection, then the Code Set Styles collection, and right-click an existing style.
Click Copy or Edit.
In the Code Set Style dialog box, click the Codes tab.
Click Import Codes.
In the drawing, click on a subassembly, assembly, or corridor object, and press Enter. The codes are automatically displayed in the Codes tab list.
Click Apply