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Namespace: Autodesk.Revit.DB

Categories

Class
Description:
The Categories object is a map that contains all the top-level Category objects within the Document.
Remarks:
Use this object to retrieve categories by name or by BuiltInCategory id.
Inheritance Hierarchy:
System.Object
  Autodesk.Revit.DB.APIObject
    Autodesk.Revit.DB.CategoryNameMap
      Autodesk.Revit.DB.Categories
Syntax
public class Categories : CategoryNameMap
Examples
// Get settings of current document
Settings documentSettings = document.Settings;

// Get all categories of current document
Categories groups = documentSettings.Categories;

// Show the number of all the categories to the user
String prompt = "Number of all categories in current Revit document:" + groups.Size;

// get Floor category according to OST_Floors and show its name
Category floorCategory = groups.get_Item(BuiltInCategory.OST_Floors);
prompt += floorCategory.Name;

// Give the user some information
TaskDialog.Show("Revit",prompt);