Extracts a collection containing the ids of elements that have been created, modified or deleted between the input baseVersion and the document's current version.

Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 24.0.0.0 (24.0.0.0)
Since:  2023

Syntax

C#
public DocumentDifference GetChangedElements(
	Guid baseVersionGUID
)
Visual Basic
Public Function GetChangedElements ( _
	baseVersionGUID As Guid _
) As DocumentDifference
Visual C++
public:
DocumentDifference^ GetChangedElements(
	Guid baseVersionGUID
)

Parameters

baseVersionGUID
Type: System..::..Guid
GUID of base version(excluded) to compare. This GUID should be retrieved from property [!:Autodesk::Revit::DB::DocumentVersion::VersoinGUID]. Empty GUID is allowed to retrieve changes of each version in the document.

Return Value

An object containing collections of the created, modified and deleted ids between the input version and current version.

Examples

CopyC#
private void ShowChangedElements(Autodesk.Revit.DB.Document document, Guid baseVerseionGuid)
{
    //Parameter baseVersionGuid is retrieved from property VersionGUID of Autodesk.Revit.DB.DocumentVersion.
    //System.Guid.Empty is allowed to get all changes in document.
    DocumentDifference docDiff = document.GetChangedElements(baseVerseionGuid);
    if (docDiff.AreDeletedElementIdsAvailable)
    {
        TaskDialog.Show("Revit", "Deleted element history is available in current document.");
    }
    else
    {
        TaskDialog.Show("Revit", "Deleted element history is not available in current document.");
    }

    // New added elements.
    var createdElementIds = docDiff.GetCreatedElementIds();

    // Modified elements.
    var modifiedElementIds = docDiff.GetModifiedElementIds();

    // Deleted elements.
    // For nonworkshared model, always returns an empty collection.
    var deletedElementIds = docDiff.GetDeletedElementIds();

    var changesetMessage = $"Found {createdElementIds.Count} new created elements, {modifiedElementIds.Count} modified elements and {deletedElementIds.Count} deleted elements.";
    TaskDialog.Show("Revit", changesetMessage);
}
CopyVB.NET
Private Sub ShowChangedElements(ByVal document As Document, ByVal baseVerseionGuid As Guid)
    'Parameter baseVersionGuid is retrieved from property VersionGUID of Autodesk.Revit.DB.DocumentVersion.
    'System.Guid.Empty is allowed to get all changes in document.
    Dim docDiff = document.GetChangedElements(baseVerseionGuid)

    If docDiff.AreDeletedElementIdsAvailable Then
        TaskDialog.Show("Revit", "Deleted element history is available in current document.")
    Else
        TaskDialog.Show("Revit", "Deleted element history is not available in current document.")
    End If

    ' New added elements.
    Dim createdElementIds = docDiff.GetCreatedElementIds()

    ' Modified elements.
    Dim modifiedElementIds = docDiff.GetModifiedElementIds()

    ' Deleted elements.
    ' For nonworkshared model, always returns an empty collection.
    Dim deletedElementIds = docDiff.GetDeletedElementIds()
    Dim changesetMessage = $"Found {createdElementIds.Count} new created elements, {modifiedElementIds.Count} modified elements and {deletedElementIds.Count} deleted elements."
    TaskDialog.Show("Revit", changesetMessage)
End Sub

Exceptions

ExceptionCondition
Autodesk.Revit.Exceptions..::..ArgumentException This GUID is invalid in the given document.

See Also