The attribute data section of an element placed with a line style contains a name ID plus any line style modifiers specified in the Line Styles dialog. The name ID identifies only the name of the line style in an ID-to-Name map that is contained in the DGN file. This name is used to obtain the resource type and ID of each line style component in the line style definition based on a Name-to-Resource ID map that is stored in the line style library, which is a resource file along with the component definitions themselves.

The name indirection is necessary to avoid the need for unique component resource IDs across many different line style libraries. It also provides a simple method for replacing line styles for different display options. Line styles can be completely replaced simply by changing line style libraries, provided the new line style library contains a compatible Name-to-Resource ID map. (Line style libraries are binary-compatible across all MicroStation platforms.) The indirection also makes it possible for a single line style component to be contained in multiple line style definitions.