Each & every graphic element in a MicroStation DGN file has a unique 64-bit ID. Element IDs are used extensively by MicroStation internally, but normally they are of little concern to users. Nonetheless, sometimes you may need to find an element given its ID.

Q How do I find an element given its ID?

A Each and every graphic element in a MicroStation DGN file has a unique ID. The ID is a 64-bit integer number. You can see an element's ID using the element information tool …

The ID is listed at the bottom of the Element Information dialog under the Raw Data category …

MicroStation CONNECT is 64-bit and provides direct support for 64-bit integer numbers such as an Element ID. VBA for MicroStation V8i does not provide intrinsic support for 64-bit numbers. MicroStation VBA V8i substitutes the DLong user-defined-type (UDT). A DLong packs two 32-bit integers into a UDT. MicroStation VBA provides a number of methods that operate on DLong.

In this example, we show how to enable a user to keyin a command and pass an element ID to the VBA code that locates an element.

Option Explicit
Option Base 0

' ---------------------------------------------------------------------
'   Main entry point.  Command-line syntax:
'   vba run [ElementLocator]modMain.Main <element id>
'   Substitute a valid MicroStation graphic element ID for  <element id>
' ---------------------------------------------------------------------
Public Sub Main()
	Dim id As DLong
	id = DLongFromString(KeyinArguments)
	Dim oTarget                     	    As Element
	On Error GoTo err_ElementNotFound
	'   Next line throws an error if the ID is not valid
	Set oTarget = ActiveModelReference.GetElementByID(id)
	ZoomToElement oTarget, 1
    Exit Sub

err_ElementNotFound:
    MsgBox "Element having ID " & DLongToString(id) & " not found", vbOKOnly Or vbInformation, "Invalid Element ID"
End Sub

' ---------------------------------------------------------------------
'   ZoomToElement
' ---------------------------------------------------------------------
Function ZoomToElement(ByVal oTarget As Element, ByVal nView As Integer) As Boolean
    ZoomToElement = False
    If (oTarget.IsGraphical) Then
        Const Zoom                          As Double = 4
        Dim range                           As Range3d
        range = oTarget.range
        Dim oView                           As View
        Set oView = ActiveDesignFile.Views.Item(nView)
        Dim extent                          As Point3d
        extent = Point3dScale(Point3dSubtract(range.High, range.Low), Zoom)
        oView.origin = Point3dSubtract(range.Low, Point3dScale(extent, 0.5))
        oView.Extents = extent
        oView.Redraw
        oTarget.IsHighlighted = True
    Else
        MsgBox "Element having ID " & DLongToString(oTarget.id) & " is not a graphical element", vbOKOnly Or vbInformation, "Invalid Element"
    End If
    Exit Function

err_ZoomToElement:
    ReportError strMODULE_NAME, "ZoomToElement"
End Function

When you run the above code, providing you pass a valid element ID, MicroStation adjusts view one to display the element.

Download VBA Project

You can download the ElementLocator.mvba project. Unpack the ZIP archive and extract ElementLocator.mvba to a well-known location such as \Bentley\Workspace\Standards\vba. Run the macro using the keyin
vba run [ElementLocator]modMain.Main <element id>, substituting a valid element ID for <element id>.