Show Thumbnail in the Windows.Forms.PictureBox iLogic Inventor 2026

[pavol_krasnansky1]

Hi, the iLogic rule below works in Inventor 2023 and does not work in Inventor 2026. Why? What should I change?

Imports System.Windows.Forms
Imports System.IO
Imports System.Windows.Imaging
Imports System.Windows.Graphics
Imports System.Drawing
Imports Microsoft.VisualBasic

AddReference "System.Drawing.dll"
AddReference "Microsoft.VisualBasic.Compatibility.dll"
AddReference "Microsoft.VisualBasic.dll"
AddReference "stdole.dll"

'--------------------------------------------------------------------------------------

Sub Main()
	
	'--------------------------------------------------------------------------------------
	
	Dim oThumbnail As IPictureDisp = ThisDoc.Document.Thumbnail
	
	'--------------------------------------------------------------------------------------
	
	' oForm
	Dim oForm As New System.Windows.Forms.Form
	oForm.Text = "Thumbnail Inventor 2026"
	oForm.Size = New Drawing.Size(350, 400)
	oForm.Font = New Drawing.Font("Arial", 10)
	' oForm.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle
	oForm.StartPosition = FormStartPosition.CenterScreen
	oForm.ShowIcon = False
	oForm.HelpButton = False
	oForm.MaximizeBox = True
	oForm.MinimizeBox = True
	oForm.Margin = New System.Windows.Forms.Padding(0, 0, 0, 0) ' Vonkajšie: Left, Top, Right, Bottom
	oForm.Padding = New System.Windows.Forms.Padding(0, 0, 0, 0) ' Vnútorné: Left, Top, Right, Bottom
	
	'--------------------------------------------------------------------------------------
	
	' TableLayoutPanel1
	Dim TableLayoutPanel1 As New System.Windows.Forms.TableLayoutPanel
	TableLayoutPanel1.ColumnCount = 1
	TableLayoutPanel1.RowCount = 1
	TableLayoutPanel1.ColumnStyles.Add(New System.Windows.Forms.ColumnStyle(System.Windows.Forms.SizeType.Percent, 100.0!))
	TableLayoutPanel1.RowStyles.Add(New System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 100.0!))
	TableLayoutPanel1.Dock = System.Windows.Forms.DockStyle.Fill
	TableLayoutPanel1.Margin = New System.Windows.Forms.Padding(5, 5, 5, 5) ' Vonkajšie: Left, Top, Right, Bottom
	TableLayoutPanel1.Padding = New System.Windows.Forms.Padding(5, 5, 5, 5) ' Vnútorné: Left, Top, Right, Bottom
	oForm.Controls.Add(TableLayoutPanel1)
	
	'--------------------------------------------------------------------------------------
	
	' oPictureBox
	Dim oPictureBox As New System.Windows.Forms.PictureBox
	oPictureBox.SizeMode = PictureBoxSizeMode.Zoom ' CenterImage
	oPictureBox.Dock = System.Windows.Forms.DockStyle.Fill
	oPictureBox.Margin = New System.Windows.Forms.Padding(5, 5, 5, 5) ' Vonkajšie: Left, Top, Right, Bottom
	oPictureBox.Padding = New System.Windows.Forms.Padding(0, 0, 0, 0) ' Vnútorné: Left, Top, Right, Bottom
	TableLayoutPanel1.Controls.Add(oPictureBox, 0, 0)
	
	Dim oThumbnail_Image As System.Drawing.Image
	oThumbnail_Image = Compatibility.VB6.IPictureDispToImage(oThumbnail)
	Dim oThumbnail_Bitmap As New Bitmap(500, 500)
	Dim oThumbnail_Resize As System.Drawing.Graphics = Graphics.FromImage(oThumbnail_Bitmap)
	
	Try
		
		oThumbnail_Resize.DrawImage(oThumbnail_Image, 0, 0, 500, 500)
		
	Catch ex As Exception
		
		'MsgBox(ex.ToString)
		
	End Try
	
	oPictureBox.Image = oThumbnail_Bitmap
	oThumbnail_Image = Nothing
	oThumbnail_Resize = Nothing
	oThumbnail_Bitmap = Nothing
	
	'--------------------------------------------------------------------------------------
	
	oForm.ShowDialog()
	
	'--------------------------------------------------------------------------------------
	
End Sub

[Andrii_Humeniuk · Accepted solution]

Hi @pavol_krasnansky1 . 
This is due to the fact that Inventor from version 2025 migrated from .Net Framework to .Net core 8. You can read more about this at the link, link. Regarding your problem, I recommend reading the following topic. If you use the tips, your code should look something like this:

Imports System.Windows.Forms
Imports System.IO
Imports System.Windows.Imaging
Imports System.Windows.Graphics
Imports System.Drawing
Imports Microsoft.VisualBasic
AddReference "System.Drawing.dll"
'AddReference "Microsoft.VisualBasic.Compatibility.dll"
AddReference "Microsoft.VisualBasic.dll"
AddReference "stdole.dll"


'--------------------------------------------------------------------------------------

Sub Main()
	
	'--------------------------------------------------------------------------------------
	
	Dim oThumbnail As IPictureDisp = ThisDoc.Document.Thumbnail
	
	'--------------------------------------------------------------------------------------
	
	' oForm
	Dim oForm As New System.Windows.Forms.Form
	oForm.Text = "Thumbnail Inventor 2026"
	oForm.Size = New Drawing.Size(350, 400)
	oForm.Font = New Drawing.Font("Arial", 10)
	' oForm.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle
	oForm.StartPosition = FormStartPosition.CenterScreen
	oForm.ShowIcon = False
	oForm.HelpButton = False
	oForm.MaximizeBox = True
	oForm.MinimizeBox = True
	oForm.Margin = New System.Windows.Forms.Padding(0, 0, 0, 0) ' Vonkajšie: Left, Top, Right, Bottom
	oForm.Padding = New System.Windows.Forms.Padding(0, 0, 0, 0) ' Vnútorné: Left, Top, Right, Bottom
	
	'--------------------------------------------------------------------------------------
	
	' TableLayoutPanel1
	Dim TableLayoutPanel1 As New System.Windows.Forms.TableLayoutPanel
	TableLayoutPanel1.ColumnCount = 1
	TableLayoutPanel1.RowCount = 1
	TableLayoutPanel1.ColumnStyles.Add(New System.Windows.Forms.ColumnStyle(System.Windows.Forms.SizeType.Percent, 100.0!))
	TableLayoutPanel1.RowStyles.Add(New System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 100.0!))
	TableLayoutPanel1.Dock = System.Windows.Forms.DockStyle.Fill
	TableLayoutPanel1.Margin = New System.Windows.Forms.Padding(5, 5, 5, 5) ' Vonkajšie: Left, Top, Right, Bottom
	TableLayoutPanel1.Padding = New System.Windows.Forms.Padding(5, 5, 5, 5) ' Vnútorné: Left, Top, Right, Bottom
	oForm.Controls.Add(TableLayoutPanel1)
	
	'--------------------------------------------------------------------------------------
	
	' oPictureBox
	Dim oPictureBox As New System.Windows.Forms.PictureBox
	oPictureBox.SizeMode = PictureBoxSizeMode.Zoom ' CenterImage
	oPictureBox.Dock = System.Windows.Forms.DockStyle.Fill
	oPictureBox.Margin = New System.Windows.Forms.Padding(5, 5, 5, 5) ' Vonkajšie: Left, Top, Right, Bottom
	oPictureBox.Padding = New System.Windows.Forms.Padding(0, 0, 0, 0) ' Vnútorné: Left, Top, Right, Bottom
	TableLayoutPanel1.Controls.Add(oPictureBox, 0, 0)
	
	Dim oThumbnail_Image As System.Drawing.Image
	oThumbnail_Image = PictureDispToImage(oThumbnail)
	Dim oThumbnail_Bitmap As New Bitmap(500, 500)
	Dim oThumbnail_Resize As System.Drawing.Graphics = Graphics.FromImage(oThumbnail_Bitmap)
	
	Try
		
		oThumbnail_Resize.DrawImage(oThumbnail_Image, 0, 0, 500, 500)
		
	Catch ex As Exception
		
		'MsgBox(ex.ToString)
		
	End Try
	
	oPictureBox.Image = oThumbnail_Bitmap
	oThumbnail_Image = Nothing
	oThumbnail_Resize = Nothing
	oThumbnail_Bitmap = Nothing
	
	'--------------------------------------------------------------------------------------
	
	oForm.ShowDialog()
	
	'--------------------------------------------------------------------------------------
	
End Sub

Public Shared Function PictureDispToImage(pictureDisp As stdole.IPictureDisp) As System.Drawing.Image
	Dim oImage As System.Drawing.Image
	If pictureDisp IsNot Nothing Then
		If pictureDisp.Type = 1 Then
			Dim hpalette As IntPtr = New IntPtr(pictureDisp.hPal)
			oImage = oImage.FromHbitmap(New IntPtr(pictureDisp.Handle), hpalette)
		End If
		If pictureDisp.Type = 2 Then
			oImage = New System.Drawing.Imaging.Metafile(New IntPtr(pictureDisp.Handle), New System.Drawing.Imaging.WmfPlaceableFileHeader())
		End If
	End If
	Return oImage
End Function