The main hyperlink classes are
An AcDbHyperlink object contains the hyperlink name (for example, https://www.autodesk.com), a sublocation within that link, the hyperlink description or friendly name (“Click here for Autodesk”), and a display string for the hyperlink. For AutoCAD, a sublocation is a named view, while in a spreadsheet application, for example, a sublocation might be a cell or group of cells. The display string is usually the same as the hyperlink's description. If the description is null, the hyperlink's name and sublocation are used instead, in “name – sublocation” format.
Hyperlinks may also have nesting levels. Nesting level is only of interest when dealing with hyperlink collections associated with an entity within a block, or with collections associated with an INSERT entity.
This class is a collection of AcDbHyperlink objects, and has a variety of methods for adding and removing those objects. The AcDbHyperlinkCollection deletes its contents when they are removed, and when the collection object itself is deleted. Hyperlinks in the collection are numbered from zero.
The methods of the AcDbEntityHyperlinkPE class allow you to set, get, and count the hyperlinks associated with an entity.