ExternalDefinition

Description:
The ExternalDefinition object adds properties specific to Autodesk Revit shared parameter definitions.

Remarks:
The ExternalDefinition object can be created by a definition Group object from a shared parameters file. External parameter definition must belong to a Group which is nothing more than a collection of shared parameter definitions. The following process should be followed to add a parameter to an element: Open the shared parameters file, via the Application.OpenSharedParameterFile() method. Access an existing or create a new group, via the DefinitionFile.Groups property. Access an existing or create a new external parameter definition, via the DefinitionGroup.Definitions property. Create a new Binding object with the categories to which the parameter will be bound using an InstanceBinding or a TypeBinding object. Finally add the binding and definition to the document using the Document.ParameterBindings object.

Inheritance Hierarchy:
System.Object
Autodesk.Revit.DB.Definition
Autodesk.Revit.DB.ExternalDefinition

public class ExternalDefinition : Definition, 
	IDisposable

Public Class ExternalDefinition _
	Inherits Definition _
	Implements IDisposable

public ref class ExternalDefinition : public Definition, 
	IDisposable

private void ReadEditExternalParam(DefinitionFile file)
{
    // get ExternalDefinition from shared parameter file
    DefinitionGroups myGroups = file.Groups;
    DefinitionGroup myGroup = myGroups.get_Item("MyGroup");
    if (myGroup != null)
    {
         ExternalDefinition myExtDef = myGroup.Definitions.get_Item("MyParam") as ExternalDefinition;
         if (myExtDef != null)
         {
             DefinitionGroup newGroup = myGroups.get_Item("AnotherGroup");
             if (newGroup != null)
             {
                 // change the OwnerGroup of the ExternalDefinition
                 myExtDef.OwnerGroup = newGroup;
             }
         }
    }
}

Private Sub ReadEditExternalParam(file As DefinitionFile)
   ' get ExternalDefinition from shared parameter file
   Dim myGroups As DefinitionGroups = file.Groups
   Dim myGroup As DefinitionGroup = myGroups.Item("MyGroup")
   If myGroup IsNot Nothing Then
      Dim myExtDef As ExternalDefinition = TryCast(myGroup.Definitions.Item("MyParam"), ExternalDefinition)
      If myExtDef IsNot Nothing Then
         Dim newGroup As DefinitionGroup = myGroups.Item("AnotherGroup")
         If newGroup IsNot Nothing Then
            ' change the OwnerGroup of the ExternalDefinition
            myExtDef.OwnerGroup = newGroup
         End If
      End If
   End If
End Sub

Name	Return Type	Description	Inherited From
M Dispose()	None	Releases all resources used by the
M GetSpecTypeId()	ForgeTypeId	Gets the identifier of the spec describing values of the parameter.	Definition

Name	Return Type	Description	Inherited From
P Description	string	The description of the parameter. The description will be used as tooltip in the Revit UI including in the properties palette.
P GUID	Guid	Returns the GUID associated with the shared parameter definition.
P HideWhenNoValue	bool	Indicates whether this parameter should be hidden from the properties palette when it has no value.
P IsValidObject	bool	Specifies whether the .NET object represents a valid Revit entity.
P Name	string	The user visible name for the parameter.
P OwnerGroup	DefinitionGroup	Returns or change the group ID of the external parameter definition.
P ParameterGroup	BuiltInParameterGroup	Returns the group ID of the parameter definition.
P ParameterType	ParameterType	Returns the user visible interpretation of the parameter data.
P UserModifiable	bool	Indicates whether the parameter can be modified by the user interface.
P Visible	bool	Indicates if the parameter is visible in the Autodesk Revit user interface.
P Name	string	The user visible name for the parameter.	Definition
P ParameterGroup	BuiltInParameterGroup	Returns the group ID of the parameter definition.	Definition
P ParameterType	ParameterType	Returns the user visible interpretation of the parameter data.	Definition
P UnitType	UnitType	Returns the UnitType of the parameter definition.	Definition