Mar 12, 2024

pyRevit Hooks: How to create EventTriggers to Block CAD Imports in Revit API?

EventTriggers are very powerful in Revit API. They allow you to subscribe to certain events and execute specific code only when this action is triggered. It opens a whole new world for automation.

What is Revit API Events or pyRevit hooks?

Event - Is an action that can be monitored by the software. This means that we can subscribe to an event, and whenever it happens we will execute a piece of our code.

pyRevit hook is a simplified way of subscribing to Events. It allows you to simply create hooks folder, and name your python file and pyRevit knows what to do next.

Why do we need Events?

When we work with Revit API we have an ability to subscribe to Events, and execute code when they are triggered. This allows you to wait for certain actions and then execute your code when it happens. It can open a whole new world of automation in Revit.

For example, we know that Import CAD is a cursed button, and many BIM managers try very hard to make everyone Link CAD files instead of importing because they bring a lot of useless patterns, and don't have an original path associated with them… So we can subscribe to a command event of Import CAD button, and whenever it's clicked we can execute our assigned code (show a warning message in this case).

This examples is exactly what I will show you how to create by the end of this lesson. But first let's explore Revit API events a bit more.

Revit API Event Types

There are a lot of events available in Revit API, and I will try to categorize and list them here starting with Database events.

1️⃣ DataBase Events (Application )

Database events are looking for changes related to the project and application state. It will monitor when projects are being saved, opened printed, exported and similar interactions. These events can be found under Application Class and here is a list of them:

2️⃣ UI Events (UIApplication)

Then we have related to Revit UI. These are about interaction with the application or certain actions being taken. All these events are located in UIApplication Class, and here is the list:

There are also Events under Autodesk.Revit.UI - PreviewControl for monitoring user's interaction like DragEnter, DragLeave…

3️⃣ CommandBinding Event

We can create Command Binding Events. This will allow us to monitor commands within Revit and subscribe to them. You can see a list of all commands in PostableCommand Enumeration, it has hundreds if not thosands of commands, so I won't list them here…

On top of that all these commands can be subscribed as:

  • BeforeExecuted- This read-only event occurs before the associated command executes. An application can react to this event but cannot make changes to documents, or affect the invocation of the command.

  • CanExecute - Occurs when the associated command initiates a check to determine whether the command can be executed on the command target.

  • Executed - This event occurs when the associated command executes and is where any overriding implementation should be performed.

💡pyRevit simplifies this step for us, but I will also show you how to manually subscribe with code, and these stages of an Event will matter.

4️⃣ IUpdater (Dynamic Model Update)

Lastly, I want to mention that there is also an IUpdater Interface. It's The interface used to create an updater capable of reacting to changes in the Revit model. It also has its hook equivalent in pyRevit doc-updater.py

Technically it's not an event, but it acts like one. It allows us to monitor changes in the project, and piggy back on the same Transaction to add our additional changes to it.

Just to give you an example how it can be used:
We can monitor changes for Windows, and whenever they change, we might want to update X,Y,Z coordinates in one of the parameters, so we can actually tag their location and it will always update as you move them.

There are endless possibilities for new functionality by using IUpdater. It's incredible useful, but I won't cover it in this lesson. It deserves a lesson of its own. Comment on the YouTube video if you want to see how to use it 😉

So how do we work with Events?

We have 2 options to subscribe to Events in Revit API.

🅰️ pyRevit Hooks - Very powerful and beginner friendly approach
🅱️ Manually Subscribe to Events - You can also write the whole code yourself to subscribe, but then it needs to be executed every time you start Revit or whenever you need it.

I will mainly focus on pyRevit hooks, but I will also show an example of doing it manually in the end.

🎯 Let's create an Event to monitor when users click on Import CAD button. And then we will give them a warning, saying that they should Link instead of importing and ask for a password, so only a select few users can import CAD files. You can apply the same concept to other buttons or other events, it's just an example I chose.

pyRevit Hooks

pyRevit provides a very simple approach to events. I will also link additional resources here that will help you understand them and see a few examples:

In a nutshell - you need to create a hooks folder in .extension folder and place your scripts for certain events. And keep in mind that naming of your scripts in that folder is very important. The name of the files will tell pyRevit what kind of event should it be subscribed to. You can see a table of all hooks in Extension Hooks.

Creating pyRevit hooks is not that complicated. It's all about creating a python file with the correct name, and writing the script that you want to execute when event gets triggered.

💡 I know it still sounds confusing, but it's not! Let me show you how to actually use it.

How to create pyRevit Hooks? (Example)

There are plenty of different hooks to choose from, but I will start with command-before-exec[<cmd-id>]. This kind of hook can subscribe to certain commands inside of Revit and trigger BEFORE it's executed.

You can see a full list of commands and how to get them in the end of this post, but I need to name it command-before-exec[ID_FILE_IMPORT].py,so it gets triggered when user click on Import CAD button.

Let's make sure our users won't import CAD to Revit Projects and only allow in Family Documents.

First of all we need to create a hook python file in a hooks folder. Make sure you name your file correctly. In my case I want to create an Event for ID_FILE_IMPORT command, so I will have to name my file command-before-exec[ID_FILE_IMPORT].py

Here is folder structure example: (.tab and lib folders are just for reference so you know where to place hooks))

💡This file in hooks folder will tell pyRevit that the script inside should subscribe to ID_FILE_IMPORT command.

And here is a simple code we are going to put inside this python hook.

Whenever a user clicks on Import CAD, it will check if Document is project or family document, and if it's a project doc, then show a warning asking to use Link CAD. Additionally, it will also prompt a TextDialog asking for a password. If they enter the right one, they will be able to import CAD inside the project. Otherwise it won't allow importing CAD, and our BIM Managers can sleep tight at night.

# -*- coding: utf-8 -*-
#⬇️ Imports
from pyrevit import revit, EXEC_PARAMS
from Autodesk.Revit.UI import TaskDialog


#📦 Variables
sender = __eventsender__ # UIApplication
args   = __eventargs__   # Autodesk.Revit.UI.Events.BeforeExecutedEventArgs
# args   = EXEC_PARAMS.event_args

doc = revit.doc
# doc = args.GetDocument()
# doc = args.Document

#🎯 MAIN
if not doc.IsFamilyDocument:
    #⚠️ Show Warning
    TaskDialog.Show('Big Brother is Watching!',
                    'Import CAD is not Allowed! Use Link CAD Instead.')

    #🔒 Ask user for Password
    from pyrevit.forms import ask_for_string
    password   = 'LearnRevitAPI.com'
    user_input = ask_for_string(prompt='Only users with a password can Import CAD.',
                                title='Import CAD Blocked')
    # ❌ Stop Execution
    if user_input != password:
        args.Cancel = True
else:
    TaskDialog.Show('Family CAD Import',
                    'Import CAD is Allowed in families!')

👀 Here is the Result of how it works in a Project. You will notice that once I write the correct password it allows me to Import CAD. But if I would write it wrong, it would not stop the command.


How to get PostableCommand Id?

Let's go a step back and figure out how did I know that I need to use ID_FILE_IMPORT Command name for Command Binding?

I've noticed that people get very creative when looking for the right name of the command ID. You can find it in your journals or even in the .xml file of your shortcuts.

But we can also use LookupPostableCommandId Method which comes from Autodesk.Revit.UI.RevitCommandId.

This method takes a PostableCommand Enumeration, which has a list of all possible commands. There are hundreds if not thosands of them.

Here is an example of how to use it:

from Autodesk.Revit.UI import RevitCommandId, PostableCommand

all_post_commands = PostableCommand.GetValues(PostableCommand)

for pc in all_post_commands: #type: PostableCommand
	try:
		rvt_com_id = RevitCommandId.LookupPostableCommandId(pc) #type: RevitCommandId
		print('{} {}'.format(str(pc).ljust(45), rvt_com_id.Name))
	except:
		print(pc)

This will give you a list of all Postable Commands.

RoofByFace                                    ID_ROOF_PICK_FACES
Soffit                                        ID_CREATE_SOFFIT_TB
LoadAsGroupIntoOpenProjects                   ID_LOAD_INTO_PROJECTS
LoadIntoProject                               ID_LOAD_INTO_PROJECTS_REBAR_SHAPE
RepeatComponent                               ID_REPEAT_COMPONENT
ConnectionSettings                            ID_STRUCTURAL_CONNECTION_SETTINGS
StructuralConnection                          ID_STRUCTURAL_CONNECTION_DIRECT_CREATION
ShowWarningsInViews                           ID_TOGGLE_STRUCTCONNECTIONS_SHOW_WARNINGS
ViewList                                      ID_NEW_VIEWLIST
LinearDimensionTypes                          ID_SETTINGS_DIMENSIONS_LINEAR
AngularDimensionTypes                         ID_SETTINGS_DIMENSIONS_ANGULAR
SplitElement                                  ID_SPLIT
SpotElevation                                 ID_SPOT_ELEVATION
SpotCoordinate                                ID_SPOT_COORDINATE
AlignmentStation                              ID_ALIGNMENT_STATION_LABEL
AlignmentStationSet                           ID_ALIGNMENT_STATION_LABEL_SET
RoofByFootprint                               ID_ROOF_FOOTPRINT
RoofByExtrusion                               ID_ROOF_EXTRUSION
RadialDimensionTypes                          ID_SETTINGS_DIMENSIONS_RADIAL
ReloadLatest                                  ID_WORKSETS_RELOAD_LATEST
Render                                        ID_PHOTO_RENDERING_VIEW
ShowHistory                                   ID_PARTITIONS_SHOW_HISTORY
SplitSurface                                  ID_SPLIT_SURFACE
DrawOnFace                                    2706
DrawOnWorkPlane                               2707
GrayInactiveWorksets                          ID_GRAY_INACTIVE_WORKSET_GRAPHICS
ImportGBXML                                   ID_ABS_IMPORT_GBXML
ExportReportsRoomOrAreaReport                 ID_ROOM_AREA_REPORT
SheetIssuesOrRevisions                        ID_SETTINGS_REVISIONS
RevisionSchedule                              ID_VIEW_NEW_REVISION_SCHEDULE
CalloutTags                                   ID_VIEWTAGSTYLES_CALLOUTTAGS
ElevationTags                                 ID_VIEWTAGSTYLES_ELEVATIONTAGS
SectionTags                                   ID_VIEWTAGSTYLES_SECTIONTAGS
FloorByFaceFloor                              ID_FLOOR_PICK_FACES
HideCategory                                  ID_VIEW_HIDE_CATEGORY
RunInterferenceCheck                          ID_INTERFERENCE_CHECK
SpecifyCoordinatesAtPoint                     ID_SPECIFY_SHARED_COORDINATES
ExportIFC                                     ID_EXPORT_IFC
SystemBrowser                                 ID_RBS_SYSTEM_NAVIGATOR
ResetAnalyticalModel                          ID_RESET_ANALYTICAL_MODEL
ExportOptionsIFCOptions                       ID_IFC_OPTIONS
ExportDWFOrDWFx                               ID_EXPORT_DWF
ExportCADFormatsDWG                           ID_EXPORT_DWG
ExportCADFormatsDXF                           ID_EXPORT_DXF
ExportCADFormatsDGN                           ID_EXPORT_DGN
ExportCADFormatsACIS_SAT                      ID_EXPORT_SAT
ExportPDF                                     ID_EXPORT_PDF
ExportCADFormatsSTL                           ID_EXPORT_STL
ExportCADFormatsOBJ                           ID_EXPORT_OBJ
OpenIFC                                       ID_IMPORT_IFC
RelinquishAllMine                             ID_RELINQUISH_ALL_MINE
MaterialTakeoff                               ID_VIEW_NEW_MATERIAL_TAKEOFF
DWFMarkup                                     ID_MARKUPS_LOAD
ImportTypes                                   IDC_COMBOBOX_CONTROL
ExportExportTypes                             ID_EXPORT_FAM_TYPES
OpenIFCOptions                                ID_IFC_IMPORT_OPTIONS
CheckMemberSupports                           ID_COMMAND_CHECK_MEMBER_SUPPORTS
AnalyticalConsistencyChecks                   ID_COMMAND_ANALYTICAL_CONSISTENCY_CHECKS
KeynoteLegend                                 ID_VIEW_NEW_KEYNOTE_LEGEND
KeynotingSettings                             ID_SETTINGS_KEYNOTING
OpenBuildingComponent                         ID_OPEN_ADSK
Web                                           ID_TRUSS_WEB_CURVE
TopChord                                      ID_TRUSS_TOP_CHORD_CURVE
BottomChord                                   ID_TRUSS_BOTTOM_CHORD_CURVE
ShapeStatus                                   ID_SHAPE_STATUS
TogglePropertiesPalette                       ID_TOGGLE_PROPERTIES_PALETTE
CoordinationModel                             ID_COORDINATION_MODEL
StatusBarWorksets                             ID_STATUSBAR_WORKSETS
StatusBarDesignOptions                        ID_STATUSBAR_DESIGNOPTIONS
ReinforcementNumbers                          ID_NUMBERING_REINF_PARTITIONS
FamilyCategoryAndParameters                   ID_OBJECTS_FAMILYHOST
ExportImagesandAnimationsWalkthrough          ID_RM_ANIMATION
ExportImagesandAnimationsSolarStudy           ID_FILE_EXPORT_SOLAR_STUDY
SunSettings                                   ID_SETTINGS_SUNANDSHADOWSSETTINGS
Grid                                          ID_OBJECTS_GRID
ArchitecturalWall                             ID_OBJECTS_WALL
Door                                          ID_OBJECTS_DOOR
Window                                        ID_OBJECTS_WINDOW
Delete                                        ID_BUTTON_DELETE
Space                                         ID_OBJECTS_MEP_SPACE
SpaceTag                                      ID_OBJECTS_MEP_SPACE_TAG
SpaceSeparator                                ID_OBJECTS_MEP_SPACE_SEPARATION
TypeProperties                                ID_EDIT_TYPE
Level                                         ID_OBJECTS_LEVEL
FramingElevation                              ID_BUTTON_BRACING_ELEVATION
ArchitecturalFloor                            ID_OBJECTS_FLOOR
Stair                                         ID_OBJECTS_STAIRS
ArchitecturalColumn                           ID_OBJECTS_COLUMN
MirrorProject                                 ID_MIRROR_PROJECT
RotateProjectNorth                            ID_ROTATE_PROJECT
Rotate                                        ID_EDIT_ROTATE
MirrorPickAxis                                ID_EDIT_MIRROR
LineWeights                                   ID_SETTINGS_PENS
ObjectStyles                                  ID_SETTINGS_OBJECTSTYLES
AnalysisDisplayStyles                         ID_SETTINGS_ANALYSIS_DISPLAY_STYLES
Snaps                                         ID_SETTINGS_SNAPPING
ProjectUnits                                  ID_SETTINGS_UNITS
StructuralPlan                                ID_VIEW_NEW_STRUCTURAL_PLAN
FloorPlan                                     ID_VIEW_NEW_PLAN
Section                                       ID_VIEW_NEW_SECTION
Camera                                        ID_VIEW_NEW_3DVIEW
ProjectBrowser                                ID_VIEW_PROJECTEXPLORER
NewSheet                                      ID_VIEW_NEW_SHEET
ImportCAD                                     ID_FILE_IMPORT
LinkCAD                                       ID_FILE_CADFORMAT_LINK
PointCloud                                    ID_POINT_CLOUD
NewFamily                                     ID_FAMILY_NEW
LoadShapes                                    ID_FAMILY_LOAD
NewConceptualMass                             ID_NEW_REVIT_DESIGN_MODEL
LoadAutodeskFamily                            ID_FAMILY_LOAD_CLOUD
Pin                                           ID_LOCK_ELEMENTS
Walkthrough                                   ID_VIEW_NEW_WALKTHROUGH
Unpin                                         ID_UNLOCK_ELEMENTS
SolidExtrusion                                ID_OBJECTS_EXTRUSION
PlaceAComponent                               ID_OBJECTS_FAMSYM
ModelLine                                     ID_OBJECTS_PROJECT_CURVE
StairPath                                     ID_OBJECTS_STAIRS_PATH
ReferencePlane                                ID_OBJECTS_CLINE
Redo                                          ID_BUTTON_REDO
Undo                                          ID_BUTTON_UNDO
Control                                       ID_OBJECTS_CONTROL
PickAPlane                                    ID_PICK_WORKPLANE
Filters                                       ID_SETTINGS_FILTERS
TemporaryDimensions                           ID_SETTINGS_DIMENSIONS
LinePatterns                                  ID_SETTINGS_PEN_FONTS
Array                                         ID_EDIT_CREATE_PATTERN
Move                                          ID_EDIT_MOVE
Copy                                          ID_EDIT_MOVE_COPY
PlaceView                                     ID_VIEW_PLACE_VIEW
Text                                          ID_OBJECTS_TEXT_NOTE
NewTitleBlock                                 ID_TITLEBLOCK_NEW
AutomaticCeiling                              ID_OBJECTS_CEILING
FillPatterns                                  ID_SETTINGS_FILLPATTERNS
Default3DView                                 ID_VIEW_DEFAULT_3DVIEW
Label                                         ID_OBJECTS_TAG_NOTE
VisibilityOrGraphics                          ID_VIEW_CATEGORY_VISIBILITY
Opening                                       ID_OBJECTS_OPENING
NewProject                                    ID_FILE_NEW_CHOOSE_TEMPLATE
ActivateView                                  ID_VIEWPORT_ACTIVATE
Materials                                     ID_SETTINGS_MATERIALS
DeactivateView                                ID_VIEWPORT_ACTIVATE_BASE
MaterialAssets                                ID_SETTINGS_RENDERING_APPEARANCE
DecalTypes                                    ID_SETTINGS_DECAL_TYPES
Options                                       ID_OPTIONS
Room                                          ID_OBJECTS_ROOM
CurtainGrid                                   ID_OBJECTS_CW_GRID
CurtainWallMullion                            ID_OBJECTS_MULLION
FamilyTypes                                   ID_FAMILY_TYPE
FilledRegion                                  ID_OBJECTS_FILLED_REGION
RoomTag                                       ID_OBJECTS_ROOM_TAG
Align                                         ID_ALIGN
Symbol                                        ID_OBJECTS_FAM_ANN_INST
DuplicateView                                 ID_PRJBROWSER_COPY
ExportOptionsExportSetupsDGN                  ID_SETTINGS_EXPORT_SETUPS_DGN
ExportOptionsExportSetupsDWGOrDXF             ID_SETTINGS_EXPORT_SETUPS_DWGDXF
ColorFillLegend                               ID_OBJECTS_ROOM_FILL
BuildingElevation                             ID_BUTTON_INTERIOR_ROOM_ELEVATION
JoinOrUnjoinRoof                              ID_JOIN_ROOF
SolidBlend                                    ID_OBJECTS_BLEND
ManageLinks                                   ID_LINKED_DWG
SolidRevolve                                  ID_OBJECTS_REVOLUTION
ScheduleOrQuantities                          ID_VIEW_NEW_SCHEDULE
Callout                                       ID_VIEW_NEW_CALLOUT
SolidSweep                                    ID_OBJECTS_SWEEP
CreateGroup                                   ID_EDIT_GROUP
Ramp                                          ID_OBJECTS_RAMP
RoomSeparator                                 ID_OBJECTS_AREA_SEPARATION
AlignedToCurrentView                          ID_EDIT_PASTE_ALIGNED
AlignedToPickedLevel                          ID_EDIT_PASTE_ALIGNED_PICK_LEVEL
WallJoins                                     ID_EDIT_WALL_JOINS
StartingView                                  ID_STARTING_VIEW
AlignedToSelectedLevels                       ID_EDIT_PASTE_ALIGNED_LEVEL_BY_NAME
TagByCategory                                 ID_BUTTON_TAG
AlignedToSelectedViews                        ID_EDIT_PASTE_ALIGNED_VIEWS_BY_NAME
LoadedTagsAndSymbols                          ID_SETTINGS_TAGS
NewAnnotationSymbol                           ID_ANNOTATION_SYMBOL_NEW
AlignedToSamePlace                            ID_EDIT_PASTE_ALIGNED_SAME_PLACE
SpotSlopeTypes                                ID_SETTINGS_SPOT_SLOPE
Arrowheads                                    ID_SETTINGS_ANNOTATIONS_LEADERS
SpotElevationTypes                            ID_SETTINGS_SPOT_ELEVATION
SpotCoordinateTypes                           ID_SETTINGS_SPOT_COORDINATE
ReviewWarnings                                ID_REVIEW_WARNINGS
AlignmentStationLabelTypes                    ID_SETTINGS_ALIGNMENT_STATION_LABEL
LineStyles                                    ID_SETTINGS_LINE_STYLES
ReflectedCeilingPlan                          ID_VIEW_NEW_RCP
DetailLevel                                   ID_DETAIL_LEVEL
VoidExtrusion                                 ID_OBJECTS_EXTRUSION_CUT
VoidBlend                                     ID_OBJECTS_BLEND_CUT
VoidRevolve                                   ID_OBJECTS_REVOLUTION_CUT
VoidSweep                                     ID_OBJECTS_SWEEP_CUT
CutGeometry                                   ID_CUT_HOST
UncutGeometry                                 ID_UNCUT_HOST
PlaceDetailGroup                              ID_OBJECTS_PLACE_DETAIL_GROUP
OverrideByCategory                            ID_VIEW_OVERRIDE_CATEGORY
DetailComponent                               ID_OBJECTS_FAMDETAIL
DetailLine                                    ID_OBJECTS_DETAIL_CURVES
Insulation                                    ID_OBJECTS_INSULATION
CreateSimilar                                 ID_EDIT_CREATE_SIMILAR
Worksets                                      ID_SETTINGS_PARTITIONS
Phases                                        ID_SETTINGS_PHASES
PropertyLine                                  ID_SITE_PROPERTYLINE
BuildingPad                                   ID_SITE_BUILDINGPAD
ImportImage                                   ID_OBJECTS_RASTER
ImportPDF                                     ID_OBJECTS_RASTER_PDF
MatchTypeProperties                           ID_EDIT_MATCH_TYPE
ScopeBox                                      ID_VOLUME_OF_INTEREST
Linework                                      ID_EDIT_LINEWORK
SetWorkPlane                                  ID_SKETCH_PLANE_TOOL
DraftingView                                  ID_VIEW_NEW_DRAFTING
Legend                                        ID_VIEW_NEW_LEGEND
Demolish                                      ID_EDIT_DEMOLISH
RevisionCloud                                 ID_OBJECTS_CLOUD
SynchronizeAndModifySettings                  ID_FILE_SAVE_TO_CENTRAL
ProjectInformation                            ID_SETTINGS_PROJECT_INFORMATION
ModelInPlace                                  ID_INPLACE_COMPONENT
SheetList                                     ID_VIEW_NEW_DRAWING_LIST
AreaPlan                                      ID_VIEW_NEW_AREASCHEME
GradedRegion                                  ID_SITE_GRADE
Toposurface                                   ID_SITE_TOPO_SURFACE
ManageImages                                  ID_EDIT_RASTER_SYMBOLS
ApplyTemplatePropertiesToCurrentView          ID_APPLY_VIEW_TEMPLATE
RevealWall                                    ID_OBJECTS_REVEAL
SweepWall                                     ID_OBJECTS_CORNICE
Paint                                         ID_EDIT_PAINT
RemovePaint                                   ID_EDIT_UNPAINT
NoteBlock                                     ID_VIEW_NEW_NOTE_BLOCK
ModelText                                     ID_OBJECTS_MODELTEXT
ShowHiddenLinesByElement                      ID_HIDE_ELEMENTS_EDITOR
RemoveHiddenLinesByElement                    ID_UNHIDE_ELEMENTS_EDITOR
ManageViewTemplates                           ID_SETTINGS_VIEWTEMPLATES
CreateTemplateFromCurrentView                 ID_CREATE_VIEW_TEMPLATE
SplitFace                                     ID_SPLIT_FACE
RestoreBackup                                 ID_FILE_BACKUPS
ExportODBCDatabase                            ID_FILE_EXPORT_ODBC
LoadAsGroup                                   ID_LOAD_GROUP
SaveAsLibraryGroup                            ID_SAVE_GROUP
ParkingComponent                              ID_SITE_PARKING_COMPONENT
TransferProjectStandards                      ID_TRANSFER_PROJECT_STANDARDS
SymbolicLine                                  ID_OBJECTS_VIEW_DIR_SPEC_CURVE
CutProfile                                    ID_EDIT_CUT_BOUNDARY
ExportReportsSchedule                         ID_FILE_EXPORT_SCHEDULE
CloseInactiveViews                            ID_VIEW_CLOSE_INACTIVE
AreaTag                                       ID_OBJECTS_AREA_TAG
AreaBoundary                                  ID_OBJECTS_AREASCHEME_BOUNDARY
Area                                          ID_OBJECTS_AREA
JoinGeometry                                  ID_JOIN_ELEMENTS_EDITOR
UnjoinGeometry                                ID_UNJOIN_ELEMENTS_EDITOR
SwitchJoinOrder                               ID_SWITCH_JOIN_ORDER_EDITOR
TagAllNotTagged                               ID_BUTTON_TAG_ALL
MergeSurfaces                                 ID_MERGE_SURFACE
SharedParameters                              ID_FILE_EXTERNAL_PARAMETERS
LegendComponent                               ID_OBJECTS_LEGEND_COMPONENT
Offset                                        ID_OFFSET
PurgeUnused                                   ID_PURGE_UNUSED
PlaceDecal                                    ID_RM_CREATE_DECAL
TitleBlock                                    ID_OBJECTS_PLACE_TITLEBLOCK
RebarLine                                     ID_OBJECTS_REBAR_CURVE
LabelContours                                 ID_SITE_LABEL_CONTOURS
SplitWithGap                                  ID_SPLIT_WITH_GAP
ThinLines                                     ID_THIN_LINES
LinkRevit                                     ID_RVTDOC_LINK
ExportImagesandAnimationsImage                ID_FILE_PRINT_TO_IMAGE
ProjectParameters                             ID_SETTINGS_PROJECT_PARAMETERS
RelocateProject                               ID_RELOCATE_SHARED_COORDINATES
RotateTrueNorth                               ID_ROTATE_SHARED_COORDINATES
DuplicateWithDetailing                        ID_DUPLICATE_WITH_DETAILING
Location                                      ID_GEO_MANAGE_LOCATIONS
AcquireCoordinates                            ID_GEO_ACQUIRE_COORDINATES
ReportSharedCoordinates                       ID_REPORT_SHARED_COORDINATES
IdsOfSelection                                ID_IDS_OF_SELECTION
SelectById                                    ID_SELECT_BY_ID
PublishCoordinates                            ID_GEO_PUBLISH_COORDINATES
ParametersService                             ID_SETTINGS_FORGE_PARAMETERS
PlanRegion                                    ID_NEW_PLAN_REGION
BrowserOrganization                           ID_BROWSER_ORGANIZATION
Matchline                                     ID_NEW_MATCHLINE
ViewReference                                 ID_NEW_REFERENCE_VIEWER
DesignOptions                                 ID_EDIT_DESIGNOPTIONS
AddToSet                                      ID_EDIT_ADDTODESIGNOPTIONSET
PickToEdit                                    ID_EDIT_PICKS_OPTION
EditingRequests                               ID_WORKSET_EDITING_REQUESTS
SaveAsLibraryFamily                           ID_SAVE_FAMILY_ANY
Subregion                                     ID_SITE_AREA
Railing                                       ID_OBJECTS_RAILING
Beam                                          ID_OBJECTS_BEAM
Brace                                         ID_OBJECTS_BRACE
StructuralColumn                              ID_OBJECTS_STRUCTURAL_COLUMN
StructuralWall                                ID_OBJECTS_STRUCTURAL_WALL
SpanDirectionSymbol                           ID_OBJECTS_SPAN_DIR_SYM
StructuralFloor                               ID_OBJECTS_SLAB
Scale                                         ID_EDIT_SCALE
Loads                                         ID_OBJECT_LOADS
StructuralSettings                            ID_STRUCTURAL_SETTINGS
ReferenceLine                                 ID_OBJECTS_REFERENCE_CURVE
RebarCoverSettings                            ID_REBAR_COVER_SETTINGS
ShowMassFormAndFloors                         ID_SHOW_MASS_STANDARD
CurtainSystemByFace                           ID_CURTA_SYSTEM_PICK_FACES
WallByFaceWall                                ID_WALL_PICK_FACES
ShowMassByViewSettings                        ID_SHOW_MASS_NO_OVERRIDE
ShowMassSurfaceTypes                          ID_SHOW_MASS_SURFACES
ShowMassZonesAndShades                        ID_SHOW_MASS_ZONES
StructuralRebar                               ID_REBAR_PLACE
CopyMonitorUseCurrentProject                  ID_COPY_WATCH_CURRENT
CopyMonitorSelectLink                         ID_COPY_WATCH_LINK
CoordinationReviewUseCurrentProject           ID_RECONCILE_CURRENT
CoordinationSelectLink                        ID_RECONCILE_LINK
Wall                                          ID_OBJECTS_CONTINUOUS_FOOTING
Isolated                                      ID_OBJECTS_ISOLATED_FOOTING
MaterialTag                                   ID_TAG_MATERIAL
CoordinationSettings                          ID_COPY_SETTINGS
Slab                                          ID_OBJECTS_FOOTING_SLAB
ElementKeynote                                ID_KEYNOTE_ELEMENT
MaterialKeynote                               ID_KEYNOTE_MATERIAL
UserKeynote                                   ID_KEYNOTE_USER
LoadSelection                                 ID_RETRIEVE_FILTERS
SaveSelection                                 ID_FILTERS_SELECTION_SAVE
EditSelection                                 ID_EDIT_SELECTIONS
ActivateControlsAndDimensions                 ID_TOGGLE_ACTIVATE_CONTROLS
ShowWorksharingMakeEditableControls           ID_TOGGLE_SHOW_MAKE_ELEMENT_EDITABLE_CONTROLS
MultiCategoryTag                              ID_TAG_MULTI
BoundaryConditions                            ID_OBJECT_BC
StructuralPathReinforcement                   ID_PATH_REIN_SKETCH
PathReinforcementSymbol                       ID_OBJECTS_PATH_REIN_SPAN_SYM
OpeningByFace                                 ID_CREATE_OPENING_BY_FACE_TB
VerticalOpening                               ID_CREATE_VERTICAL_OPENING_TB
DormerOpening                                 ID_CREATE_DORMER_OPENING_TB
WallOpening                                   ID_CREATE_WALL_OPENING_TB
ShaftOpening                                  ID_CREATE_SHAFT_OPENING_TB
SpotSlope                                     ID_SPOT_SLOPE
HideElements                                  ID_VIEW_HIDE_ELEMENTS
ToggleRevealHiddenElementsMode                ID_VIEW_FRAME_REVEALHIDDEN
OverrideByElement                             ID_VIEW_OVERRIDE_ELEMENTS
OverrideByFilter                              ID_VIEW_GO_FILTER
DuplicateAsDependent                          ID_CREATE_DEPENDENT_VIEW
MaskingRegion                                 ID_MASKING_REGION
MajorSegment                                  ID_MAJOR_SEGMENT
ReinforcementSettings                         ID_REBAR_ABBREVIATION
ExportFBX                                     ID_EXPORT_FBX
OpenFamily                                    ID_FAMILY_OPEN
CreateParts                                   ID_CREATE_PARTS
ViewCube                                      ID_SHOW_VIEWCUBE
BeamAnnotations                               ID_BEAM_ANNOTATION_PLACEMENT
AllowableBarTypes                             ID_REBAR_SHAPE_ALLOWABLE_BAR_TYPES
MacroManager                                  ID_TOOLS_MACROS
MacroSecurity                                 ID_TOOLS_MACROSECURITY
NavigationBar                                 ID_NAVIGATION_BAR
FormWorkPlaneView                             ID_WORKPLANE_VIEW
ReconcileHosting                              ID_TOGGLE_HOST_BY_LINK_BROWSER
AdjustAnalyticalModel                         ID_AM_EDIT_MODE_START
DiameterDimension                             ID_ANNOTATIONS_DIMENSION_DIAMETER
DiameterDimensionTypes                        ID_SETTINGS_DIMENSIONS_DIAMETER
StructuralFabricArea                          ID_FABRIC_DISTR_SYSTEM_SKETCH
FabricReinforcementSymbol                     ID_FABRIC_SYSTEM_PLACE_SPANSYMBOL
PlaceOnStairOrRamp                            ID_OBJECTS_RAILING_ON_HOST
DuctPressureLossReport                        ID_MEP_DUCT_PRESSURE_LOSS_REPORT
PipePressureLossReport                        ID_MEP_PIPE_PRESSURE_LOSS_REPORT
OpenSampleFiles                               ID_SAMPLES_OPEN
SingleFabricSheetPlacement                    ID_FABRIC_SINGLE_PLACEMENT
AlignedMultiRebarAnnotation                   ID_MULTI_REFERENCE_ANNOTATION_ALIGNED
LinearMultiRebarAnnotation                    ID_MULTI_REFERENCE_ANNOTATION_LINEAR
FabricationSettings                           ID_MEP_FABRICATION_SETTINGS
LinkIFC                                       ID_IFC_LINK
SelectionBox                                  ID_VIEW_APPLY_SELECTION_BOX
StructuralRebarCoupler                        ID_REBAR_COUPLER
PAndIDModeler                                 ID_MEP_PNID_MODELER
PAndIDSettings                                ID_MEP_PNID_SETTINGS
TogglePAndIDModelerBrowser                    ID_MEP_TOGGLE_PNID_BROWSER
DuctAccessory                                 ID_RBS_MECHANICAL_ACCESSORY
AirTerminal                                   ID_RBS_MECHANICAL_DIFFUSER
Duct                                          ID_RBS_MECHANICAL_DUCT
MechanicalEquipment                           ID_RBS_MECHANICAL_EQUIPMENT
DuctFitting                                   ID_RBS_MECHANICAL_FITTING
FlexDuct                                      ID_RBS_MECHANICAL_FLEX
ConvertToFlexDuct                             ID_RBS_MECHANICAL_CONVERTTOFLEX
DuctLegend                                    ID_RBS_MECHANICAL_COLOR_FILL
PanelSchedules                                ID_RBS_VIEW_PANEL_SCHEDULE
ElectricalSettings                            ID_RBS_ELECTRICAL_SETTINGS
LoadClassifications                           ID_RBS_ELECTRICAL_LOAD_CLASSIFICATION
LightingFixture                               ID_RBS_LIGHTING_FIXTURE
ElectricalEquipment                           ID_RBS_ELECTRICAL_EQUIPMENT
ElectricalFixture                             ID_RBS_ELECTRICAL_DEVICE
CheckCircuits                                 ID_RBS_CHECK_CIRCUITS
DemandFactors                                 ID_RBS_ELECTRICAL_DEMAND_FACTOR
Pipe                                          ID_RBS_PIPE_PIPE
FlexPipe                                      ID_RBS_PIPE_FLEX
PipeFitting                                   ID_RBS_PIPE_FITTING
PipeAccessory                                 ID_RBS_PIPE_ACCESSORY
ArcWire                                       ID_RBS_ELECTRICAL_WIRE
PipeLegend                                    ID_RBS_PIPING_COLOR_FILL
CheckPipeSystems                              ID_RBS_CHECK_PIPE_SYSTEMS
CheckDuctSystems                              ID_RBS_CHECK_DUCT_SYSTEMS
MechanicalSettings                            ID_RBS_MECHANICAL_SETTINGS
PlumbingFixture                               ID_RBS_PLUMBING_FIXTURE
Sprinkler                                     ID_RBS_SPRINKLER
ElectricalConnector                           ID_RBS_ADD_ELECTRICAL_CONNECTOR
DuctConnector                                 ID_RBS_ADD_DUCT_CONNECTOR
PipeConnector                                 ID_RBS_ADD_PIPE_CONNECTOR
Zone                                          ID_RBS_HVAC_ZONE
BuildingOrSpaceTypeSettings                   ID_RBS_BUILDINGSPACE_TYPE_SETTINGS
ChamferedWire                                 ID_RBS_ELECTRICAL_WIRE_CHAMFER
SplineWire                                    ID_RBS_ELECTRICAL_WIRE_SPLINE
Communication                                 ID_RBS_ELECTRICAL_COMMUNICATION_DEVICE
Data                                          ID_RBS_ELECTRICAL_DATA_DEVICE
FireAlarm                                     ID_RBS_ELECTRICAL_FIREALARM_DEVICE
Lighting                                      ID_RBS_ELECTRICAL_LIGHTING_DEVICE
NurseCall                                     ID_RBS_ELECTRICAL_NURSECALL_DEVICE
Security                                      ID_RBS_ELECTRICAL_SECURITY_DEVICE
Telephone                                     ID_RBS_ELECTRICAL_TELEPHONE_DEVICE
CableTrayConnector                            ID_RBS_ADD_CABLETRAY_CONNECTOR
ConduitConnector                              ID_RBS_ADD_CONDUIT_CONNECTOR
CableTrayFitting                              ID_RBS_CABLETRAY_FITTING
ConduitFitting                                ID_RBS_CONDUIT_FITTING
CableTray                                     ID_RBS_CABLE_TRAY
Conduit                                       ID_RBS_CONDUIT
ManageTemplates                               ID_RBS_PANEL_SCHEDULE_MANAGE_TEMPLATES
EditATemplate                                 ID_RBS_PANEL_SCHEDULE_EDIT_A_TEMPLATE
ParallelConduits                              ID_PARALLEL_CONDUIT
DuctPlaceholder                               ID_DUCT_1LINE_PATH
PipePlaceholder                               ID_PIPE_1LINE_PATH
ParallelPipes                                 ID_PARALLEL_PIPES
ShowDisconnects                               ID_SHOWDISCONNECTS_BUTTON
MultiPointRouting                             ID_FABRICATION_PART_START_MPR
SystemZone                                    ID_MEP_CREATE_SYSTEM_ZONE
SiteComponent                                 ID_SITE_COMPONENT
AreaAndVolumeComputations                     ID_SETTING_AREACALCULATIONS
ShowWorkPlane                                 ID_SKETCH_GRID_VIS
Fascia                                        ID_CREATE_FASCIA_TB
Gutter                                        ID_CREATE_GUTTER_TB
SlabEdgeFloor                                 ID_CREATE_SLAB_EDGE_TB
CheckSpelling                                 ID_CHECK_SPELLING
RepeatingDetailComponent                      ID_OBJECTS_REPEATING_DETAIL
InsertViewsFromFile                           ID_INSERT_VIEWS_FROM_FILE
Insert2DElementsFromFile                      ID_INSERT_2D_ELEMENTS_FROM_FILE
SaveAsLibraryView                             ID_SAVE_VIEWS_TO_FILE
AutomaticBeamSystem                           ID_OBJECTS_JOIST_SYSTEM
PlaceMass                                     ID_OBJECTS_MASS
InPlaceMass                                   ID_INPLACE_MASS
SynchronizeNow                                ID_FILE_SAVE_TO_CENTRAL_SHORTCUT
StructuralTrusses                             ID_OBJECTS_TRUSS
CreateAnAreaBasedLoad                         IDS_RBS_ANALYTICAL_LOADZONE
AreaBasedLoadBoundary                         ID_RBS_ANALYTICAL_AREA_BASED_LOAD_BOUNDARY
EquipmentLoad                                 ID_RBS_ELECTRICAL_ANALYSIS_ADD_EQUIPMENT_LOAD
ShowBoundaryOpenEnds                          ID_RBS_SHOW_ABL_SEPARATION_LINE_OPEN_END
MechanicalControlDevice                       ID_RBS_MECHANICAL_CONTROL_DEVICE
PlumbingEquipment                             ID_RBS_PLUMBING_EQUIPMENT
HideBoundaryOpenEnds                          ID_RBS_HIDE_ABL_SEPARATION_LINE_OPEN_END
ShowLastReport                                ID_INTERFERENCE_REPORT
GraphicalColumnSchedule                       ID_VIEW_NEW_GRAPH_SCHED_COLUMN
ApplyCoping                                   ID_COPING
RemoveCoping                                  ID_UNCOPING
BeamSystemSymbol                              ID_OBJECTS_BEAM_SYSTEM_TAG
StructuralAreaReinforcement                   ID_REBAR_SYSTEM_SKETCH
AreaReinforcementSymbol                       ID_OBJECTS_REBAR_SYSTEM_SPAN_SYM
SolidSweptBlend                               ID_OBJECTS_SWEPTBLEND
VoidSweptBlend                                ID_OBJECTS_SWEPTBLEND_CUT
EditRebarCover                                ID_CONCRETE_COVER
ColorSchemes                                  ID_SETTINGS_COLORFILLSCHEMES
CreateAnalyticalLink                          ID_CREATE_ANALYTICAL_LINK
TrimOrExtendToCorner                          ID_TRIM_EXTEND_CORNER
TrimOrExtendSingleElement                     ID_TRIM_EXTEND_SINGLE
TrimOrExtendMultipleElements                  ID_TRIM_EXTEND_MULTIPLE
AlignedDimension                              ID_ANNOTATIONS_DIMENSION_ALIGNED
LinearDimension                               ID_ANNOTATIONS_DIMENSION_LINEAR
AngularDimension                              ID_ANNOTATIONS_DIMENSION_ANGULAR
RadialDimension                               ID_ANNOTATIONS_DIMENSION_RADIAL
ArcLengthDimension                            ID_ANNOTATIONS_DIMENSION_ARCLENGTH
MeasureBetweenTwoReferences                   ID_MEASURE_LINE
MeasureAlongAnElement                         ID_MEASURE_PICK_LINES
MirrorDrawAxis                                ID_EDIT_MIRROR_LINE
KeyboardShortcuts                             ID_KEYBOARD_SHORTCUT_DIALOG
BeamOrColumnJoins                             ID_EDIT_BEAM_JOINS
SaveAsTemplate                                ID_REVIT_SAVE_AS_TEMPLATE
SaveAsFamily                                  ID_REVIT_SAVE_AS_FAMILY
HalftoneOrUnderlay                            ID_SETTINGS_HALFTONE
Multiplanar                                   ID_TURN_ON_MULTI_PLANAR_SHAPE
OpenProject                                   ID_APPMENU_PROJECT_OPEN
LoadCases                                     ID_STRUCTURAL_SETTINGS_LOAD_CASES
LoadCombinations                              ID_STRUCTURAL_SETTINGS_LOAD_COMB
BoundaryConditionsSettings                    ID_STRUCTURAL_SETTINGS_BOUND_COND
FindOrReplace                                 ID_FIND_REPLACE
EnergySettings                                ID_CEA_VIEW_ENERGY_DATA
Generate                                      ID_CEA_LAUNCH_ANALYSIS
ExportGBXML                                   ID_EXPORT_GBXML
GuideGrid                                     ID_CREATE_GUIDE_GRID
CreateAssembly                                ID_CREATE_ASSEMBLY
StairTreadOrRiserNumber                       ID_STAIRS_TRISER_NUMBER
ManageConnectionToARevitServerAccelerator     ID_MANAGE_CONNECTION_TO_A_REVIT_SERVER_ACCELERATOR
RenderInCloud                                 ID_PHOTO_RENDER_IN_CLOUD
RenderGallery                                 ID_PHOTO_RENDER_GALLERY
CreateEnergyModel                             ID_ENABLE_ENERGY_ANALYSIS
DisplaceElements                              ID_DISPLACEMENT_CREATE
GlobalParameters                              ID_SETTINGS_GLOBAL_PARAMETERS
Collaborate                                   ID_COLLABORATE
CollaborateInCloud                            ID_COLLABORATE_360
PublishSettings                               ID_VIEWS_FOR_A360
AssemblyCode                                  ID_SETTINGS_ASSEMBLY_CODE
RevealObstacles                               ID_PATH_OF_TRAVEL_SHOW_OBSTACLES
PathOfTravel                                  ID_PATH_OF_TRAVEL
MultipleValuesIndication                      ID_MULTIPLE_VALUES_INDICATOR_SETTINGS
MultiplePaths                                 ID_MULTIPLE_PATHS
OneWayIndicator                               ID_ONE_WAY_INDICATOR
PeopleContent                                 ID_PEOPLE_CONTENT
SpatialGrid                                   ID_SPATIAL_GRID
LoadFamilyIntoProjectAndClose                 ID_LOAD_INTO_PROJECTS_CLOSE
FabricationPart                               ID_TOGGLE_FABPART_BROWSER
LoadRebarShapeIntoProjectAndClose             ID_LOAD_INTO_PROJECTS_CLOSE_REBAR_SHAPE
Dynamo                                        ID_VISUAL_PROGRAMMING_DYNAMO
DeleteEnergyModel                             ID_DISABLE_ENERGY_ANALYSIS
Shorten                                       ID_CREATE_EXT_ENTITY_SHORTENING
CopeSkewed                                    ID_CREATE_EXT_ENTITY_BEAM_COPE
CornerCut                                     ID_CREATE_EXT_ENTITY_CORNER_CUT
Welds                                         ID_CREATE_EXT_ENTITY_WELD
Plate                                         ID_CREATE_EXT_ENTITY_PLATE
Bolts                                         ID_CREATE_EXT_ENTITY_BOLT
Holes                                         ID_CREATE_EXT_ENTITY_HOLE
Anchors                                       ID_CREATE_EXT_ENTITY_ANCHOR
ShearStuds                                    ID_CREATE_EXT_ENTITY_SHEAR_STUD
ContourCut                                    ID_CREATE_EXT_ENTITY_CONTOUR
Cope                                          ID_STEEL_PARAM_CUT_COPE
Miter                                         ID_STEEL_PARAM_CUT_MITER
SawCutFlange                                  ID_STEEL_PARAM_CUT_SAW_CUT_FLANGE
SawCutWeb                                     ID_STEEL_PARAM_CUT_SAW_CUT_WEB
CutThrough                                    ID_STEEL_PARAM_CUT_THROUGH
CutBy                                         ID_STEEL_PARAM_CUT_BY
ToggleHome                                    ID_REVIT_MODEL_BROWSER
SaveAsCloudModel                              ID_REVIT_FILE_SAVE_AS_CLOUD_MODEL
SystemsAnalysis                               ID_RUN_SYSTEMS_ANALYSIS
LinkPDF                                       ID_LINK_PDF
LinkImage                                     ID_LINK_IMAGE
AnalyticalMember                              ID_ANALYTICAL_MODEL_MEMBERS
BatchPrint                                    ID_BATCH_PRINT
WorksharingMonitor                            ID_WORKSHARING_MONITOR
SharedViews                                   ID_SHARED_VIEWS
ResetSharedCoordinates                        ID_RESET_SHARED_COORDINATES
ElectricalAnalyticalLoadTypeSettings          ID_MEP_ELECTRICAL_ANALYSIS_SETTINGS
GenerateAnalysis                              ID_SYSTEMS_ANALYSIS_INSIGHT
ViewAnalysis                                  ID_SYSTEMS_ANALYSIS_RESULTS_INSIGHT
OpenCloudModel                                ID_FILE_OPEN_CLOUD_MODEL
DynamoPlayerForSteel                          ID_STEEL_PLAYLIST_DYNAMO
PanelByBoundary                               ID_CREATE_ANALYTICAL_MODEL_PANEL
AnalyticalAutomation                          ID_ANALYTICAL_AUTOMATION_PLAYLIST_DYNAMO
PanelByExtrusion                              ID_CREATE_ANALYTICAL_MODEL_PANEL_BY_EXTRUSION
SpaceNaming                                   ID_MEP_SPACE_NAMING_UTILITY
DynamoPlayer                                  ID_PLAYLIST_DYNAMO
RepairCentralModel                            ID_REPAIR_CENTRAL_MODEL
LinkTopography                                ID_TOPOGRAPHY_LINK
Optimize                                      ID_CEA_OPTIMIZE
OpenRevitFile                                 ID_REVIT_FILE_OPEN
Close                                         ID_REVIT_FILE_CLOSE
Save                                          ID_REVIT_FILE_SAVE
SaveAsProject                                 ID_REVIT_FILE_SAVE_AS
PrintSetup                                    ID_REVIT_FILE_PRINT_SETUP
Print                                         ID_REVIT_FILE_PRINT
PrintPreview                                  ID_REVIT_FILE_PRINT_PREVIEW
CopyToClipboard                               ID_EDIT_COPY
CutToClipboard                                ID_EDIT_CUT
PasteFromClipboard                            ID_EDIT_PASTE
TabViews                                      ID_VIEW_TAB
TileViews                                     ID_WINDOW_TILE_VERT
ExitRevit                                     ID_APP_EXIT
StatusBar                                     ID_VIEW_STATUS_BAR

You can also get this list of all these commands by using
pyRevit -> Spy -> List Elements -> System Postable Commands

How to Subscribe to Events Manually?

Lastly, here is an example on how to subscribe to events manually. pyRevit takes this step from us, and makes it even nicer to manage it in a folder. But you might want to know how it's used too.

You need to do the following steps:

1️⃣ Create a functions that will be subscribed to an event. I called it import_replacement in my example
2️⃣ Get Command Id with LookupCommandId or LookupPostableCommandId
3️⃣ CreateAddInCommandBinding
4️⃣
Now you can subscribe your function to this command. Make sure you select from BeforeExecuted, CanExecute, Executed Events.

Here is an Example:

# Imports
from Autodesk.Revit import UI
from Autodesk.Revit.DB import *

# .NET
import clr
clr.AddReference('System')
from System import EventHandler


# Define the function for EventTrigger
def import_replacement(sender, args):
    TaskDialog.Show('Stop!', 'Do not import!')


# Main
uiapp     = __revit__
commandId = UI.RevitCommandId.LookupCommandId("ID_FILE_IMPORT")
#commandId = UI.RevitCommandId.LookupPostableCommandId(POstableCommand.ImportCAD)

# Try to create a binding for the import command
try:
    import_binding = uiapp.CreateAddInCommandBinding(commandId)
    import_binding.BeforeExecuted += EventHandler[UI.Events.ExecutedEventArgs](import_replacement)
except:
    import traceback
    print(traceback.format_exc())

You can use RevitPythonShell to test it. But keep in mind that this event handler will work until you restart Revit or unsubscribe from an event. To unsubscribe from the event, you can use the same code and only change += to -= like this:

import_binding.Executed -= EventHandler[UI.Events.ExecutedEventArgs](eventhandler_file_import)

Happy Coding!

Congratulations!
You've just unlocked a new achievement and you can use pyRevit Hooks and Revit API Events!

Want to Learn More?

🔥 Amazing Revit API Resources!

Join Revit API

Newsletter Today!

Join Us!

which is already read by 4000+ people!

Get short Revit API Lessons and Tips directly in your mail!