A class contains reference to Application and View which are needed by external command.

Namespace: Autodesk.Revit.UI
Assembly: RevitAPIUI (in RevitAPIUI.dll) Version: 21.0.0.0 (21.1.1.109)

Syntax

C#
`public class ExternalCommandData : APIObject`

Visual Basic
`Public Class ExternalCommandData _ Inherits APIObject`

Visual C++
`public ref class ExternalCommandData : public APIObject`

Inheritance Hierarchy

System Object
Autodesk.Revit.DB APIObject
Autodesk.Revit.UI ExternalCommandData