show DWG file thumbnail image

[mjohnston.26901]

The code seems simple enough but the "acThumbnailReader" is not declared in the code given and I have no idea what to declare it "As". Help? Thanks for the code link BTW

Coolmo,
acThumbnailReader is the class contained in the download. I'm not a VB.NET guy but in C# I just call the methods of acThumnailReader. The methods are static so the class doesn't have to be instantiated (declared).

On the subject of multiple forums etc. - Aren't you glad I don't feel the same way? Either I wouldn't have found Keith's awesome solution or I wouldn't have posted an answer to your question. I had been away from this forum for a while but I'm glad I came back. There is a nice group here. I also frequent the Swamp and the Adesk forums and try to participate in all of them.

[Coolmo]

Coolmo,
acThumbnailReader is the class contained in the download. I'm not a VB.NET guy but in C# I just call the methods of acThumnailReader. The methods are static so the class doesn't have to be instantiated (declared).

On the subject of multiple forums etc. - Aren't you glad I don't feel the same way? Either I wouldn't have found Keith's awesome solution or I wouldn't have posted an answer to your question. I had been away from this forum for a while but I'm glad I came back. There is a nice group here. I also frequent the Swamp and the Adesk forums and try to participate in all of them.

Thanks for the info. I'll dig further into your link. Ed also mentioned that the answer was there. Thank you.

Again, I'm not trying to make people mad or NOT give credit where credit is due but the previous post I quoted and responded to just seemed a little sarcastic like I was some ungrateful... whatever... that didn't appreciate the link or the original poster of the link. Not true... but maybe I took it wrong. I apologize if I did. I still think the answer, when found, should be posted into this forum for the Augi masses as well. I'm also a member of the Autodesk forum but I mostly search and answer here.

[Jeff H]

Is the Attached picture what you are looking for

[Jeff H]

Here is link to the VB.Net solution
http://www.theswamp.org/index.php?topic=34923.0

[Coolmo]

Here is link to the VB.Net solution
http://www.theswamp.org/index.php?topic=34923.0

Thanks for the link and code. Apparently I've touched a nerve with these guys/gals per their posts and replys. I will appoligize to Kerry... Sorry for any confusion or bad vibes Kerry, but I also tried to find the code which everyone was talking about and the only thing I found missing was a download that 'The Swamp" said I was not allowed to download (acThumnailViewer.zip or something) so I couldn't get it to work. With that... another brick wall. I assume that if I signed up for their forum I could download it but quotes like (and joyful replys to)...

"Another Useless Group of Individuals" refering to the AUGI forum kinda turns me away, not to mention the code that was held hostage with the terms of an apology. I can't believe what this simple quest for code has turned into. Thanks for smacking down those who wanna learn.

[Jeff H]

Hey man I did not mean anything by it. I think AUGI is a great place and it would be great if everyone learning AutoCAD's API were all at the same place, but each fourm has a certian feel or vibe to it due to the member's and administraitor's. And people perfer certain one's

I know how annoying it is to find information on the API, a little snag that stops a project, or finding what to P/Invoke etc....... And most of the time it is from something simple but you can not find any documentation on it.

From your post It easy to tell that you eager and motivated to learn, and it was the wrong to go about it and i apoligize, but it was basiclly to tell you that if you can't get a answer here come ask it at the swamp, and there are plenty of people who would be glad to help out. Same goes for people at the Swamp I am sure when they can not find a answer there they come here because each forum is full of smart guys and gals.

Again I apologize and I will make sure you are able to get a image on a PictureBox because that is what is about helping each other learn.

Also I have messed around with Standard details library that fills a Listview on a tool pallete. Basiclly it will fill the Listview(if you are not fimiliar with a listview a generic way of explaining it would be the right side window of window explorer) and names the images by drawing name(minus the extension) and groups them under a title named by each Sub-Directory Name. You chose different views list,details etc....
When you double click it on a pic it will bring in all entities from that drawing in etc... with different settings to choose from. If this is something that would help.

I am not sure what type of applacation this is for but I would be glad to help out if need it because I will learn things from you and it is always better to get other's input.

I am not sure if you have VS2010 but I will load it up here. It would be Simple to change to VS2008

This would not be considered anything worth using for any buisness application due to no error handleing or that way it get's the files.....etc it was just to quickly fill a picture box with an image.


Anyways here is code behind the form. It is very basic. 95% of the code is handling the right click menu. And the bottom half is thumbnail reader class that fills another picture box.
You can use the thumbnail reader class outside of AutoCAD to get the Thumbnail. AutoCAD does not have to be installed to get Bitmap.


There are some other tricks to grabbing them so you can go another route
This will only work if you have the same name and settings on a form

Please reply back with anything you need help with

Imports System.IO
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.ApplicationServices.Application
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Runtime
Imports System.Drawing
Public Class FillPictureBoxForm

    Private Sub FillPictureBoxForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        FillCombo()
    End Sub

    'Fills the Combo Box
    Private Sub FillCombo()
        ''Because this method is called for differnt reasons
        ''and if you change 
        cboFileNmae.Items.Clear()

        Dim rootFolder As String = My.MySettings.Default.RootFolder
        If Directory.Exists(rootFolder) Then
            If My.MySettings.Default.SearchSub Then
                For Each dwgFile As String In Directory.GetFiles(rootFolder, "*.dwg", SearchOption.AllDirectories)
                    cboFileNmae.Items.Add(dwgFile)
                Next
            Else
                For Each dwgFile As String In Directory.GetFiles(rootFolder, "*.dwg")
                    cboFileNmae.Items.Add(dwgFile)
                Next
            End If

        End If
    End Sub
 
    'When the comboBox Changes It Changes the File Preview
    Private Sub cboFileNmae_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cboFileNmae.SelectedIndexChanged

        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''This gets the filename from the combobox 
        ''Which is a terrible way to do it there are better ways
        Dim fName As String = cboFileNmae.Text
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        '''''This is the code that fills the pictureBox
        Dim db As Database = New Database(False, False)
        db.ReadDwgFile(fName, FileOpenMode.OpenForReadAndReadShare, False, "")
        Dim tmbNail As Bitmap = db.ThumbnailBitmap
        picBoxThumbnail.Image = tmbNail
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        '' ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        ''''' This is a call to the thumbnail reader you would need this one if you did not have autocad runnig
        picBoxJGR.Image = ThumbnailReader.GetThumbnail(fName)
        ' ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
        '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''       
    End Sub


#Region "ContextMenu"  ''Code for Right Click Menu  
    '' Handle the the True and False Check Status whenever it is Opening
    Private Sub ContexMenu_Opening(ByVal sender As System.Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles ContexMenu.Opening
        TrueToolStripMenuItem.Checked = My.MySettings.Default.SearchSub
        FalseToolStripMenuItem.Checked = Not TrueToolStripMenuItem.Checked

    End Sub
    ''Code for Selecting Root Folder to Look in Dwgs
    Private Sub SelectFolderToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SelectFolderToolStripMenuItem.Click
        '' Save the settings this way so they persist and will save what
        ''folder you chose to be used next time you run autocad
        If FBD.ShowDialog = Windows.Forms.DialogResult.OK Then
            My.MySettings.Default.RootFolder = FBD.SelectedPath
            My.MySettings.Default.Save()
            FillCombo()
        End If
    End Sub
    ''If you set to true then will search all sub Directories of Root Folder
    Private Sub TrueToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TrueToolStripMenuItem.Click
        My.MySettings.Default.SearchSub = True
        My.MySettings.Default.Save()
        TrueToolStripMenuItem.Checked = True
        FalseToolStripMenuItem.Checked = False
        FillCombo()
    End Sub
    ''If you set to false then will not search all sub Directories of Root Folder
    Private Sub FalseToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles FalseToolStripMenuItem.Click
        My.MySettings.Default.SearchSub = False
        My.MySettings.Default.Save()
        TrueToolStripMenuItem.Checked = False
        FalseToolStripMenuItem.Checked = True
        FillCombo()
    End Sub
#End Region

    '''''''''''''''''''''''''''''''''''''''''''''''''''
End Class

[Jeff H]

It would not all fit so here is the thumbnail reader, there is no error handling
and this one sometimes will throw a eBadheader error
And here is the solution
Again there can be many improvments made so please reply with any questions are problems

When you run it right click the form and select the folder to load the files from
The way it is implemented I would not choose a folder with over a 100 drawings or set search sub-folders to true with alot of nested folders

also after netload you can just type showf then press tab until the commnad comes up

''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
''';'' Thumbnail reader class
Friend NotInheritable Class ThumbnailReader
''''''''''
    <System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)> _
    Private Structure tagBITMAPFILEHEADER

        Public bfType As UShort

        Public bfSize As UInteger

        Public bfReserved1 As UShort

        Public bfReserved2 As UShort

        Public bfOffBits As UInteger
    End Structure

    Friend Shared Function GetThumbnail(ByVal filename As String) As Bitmap

        Using fs As FileStream = File.OpenRead(filename)
            Using br As BinaryReader = New BinaryReader(fs)
                Dim datLoc As Integer
                Dim bytCnt As Byte

                ' TODO
                ' Modificar para leer directamente el centinela
                fs.Seek(13, SeekOrigin.Begin)
                datLoc = br.ReadInt32()
                datLoc += 20
                fs.Seek(datLoc, SeekOrigin.Begin)
                bytCnt = br.ReadByte()

                If bytCnt <= 1 Then
                    Return Nothing
                End If

                Dim imgHeaderStart As Int32
                Dim imgHeaderSize As Int32
                Dim imgCode As Byte

                For i As Short = 1 To bytCnt

                    imgCode = br.ReadByte()
                    imgHeaderStart = br.ReadInt32()
                    imgHeaderSize = br.ReadInt32()

                    If imgCode = 2 Then
                        fs.Seek(imgHeaderStart, SeekOrigin.Begin)

                        '-----------------------------------------------------
                        ' TODO
                        ' Deberia comprobar si asi es mas rapido, o leer cada bloque uno a uno
                        Dim bmpHeader(40) As Byte
                        bmpHeader = br.ReadBytes(40)

                        Dim biBitCount As UShort = BitConverter.ToUInt16(New Byte() {bmpHeader(14), bmpHeader(15)}, 0)
                        Dim biSizeImage As UInteger = BitConverter.ToUInt16(New Byte() {bmpHeader(20), bmpHeader(21), bmpHeader(22), bmpHeader(23)}, 0)
                        '-----------------------------------------------------

                        fs.Seek(imgHeaderStart, SeekOrigin.Begin)

                        Dim bytBMPBuff(imgHeaderSize) As Byte
                        bytBMPBuff = br.ReadBytes(imgHeaderSize)

                        Dim clrTableSize As UInteger = CUInt(If(biBitCount < 9, 4 * (2 ^ biBitCount), 0))
                        Dim bfHeader As tagBITMAPFILEHEADER

                        With bfHeader
                            .bfType = &H4D42
                            .bfSize = CUInt(54) + clrTableSize + biSizeImage
                            .bfOffBits = CUInt(54) + clrTableSize
                        End With

                        Using ms As New MemoryStream

                            Using bw As BinaryWriter = New BinaryWriter(ms)
                                bw.Write(bfHeader.bfType)
                                bw.Write(bfHeader.bfSize)
                                bw.Write(bfHeader.bfReserved1)
                                bw.Write(bfHeader.bfReserved2)
                                bw.Write(bfHeader.bfOffBits)
                                bw.Write(bytBMPBuff)

                                Dim bm As Bitmap = New Bitmap(ms)
                                Return bm
                            End Using

                        End Using



                    ElseIf imgCode = 3 Then

                        Return Nothing
                    End If

                Next

            End Using
        End Using

        Return Nothing
    End Function

End Class

[Jeff H]

I just noticed your post said listbox for some reason I thought it said comboBox can change it to a list box if need be

[Coolmo]

I just noticed your post said listbox for some reason I thought it said comboBox can change it to a list box if need be

I just wanted to populate a listbox with DWG files from a certain folder, which I have the code for working seamlessly, but then I simply wanted to be able to click a filename within the listbox and have its thumbnail image appear in a small picturebox above the list. I'm use to passing the filename to the old school OCX drawing preview and was hoping VB.NET was just as easy. Thanks for all the help on this. I'll start diving into your code soon. Hopefully no hard feelings on ANY of this. Thanks again.

[Jeff H]

None at all this one is alot smaller and more what you said you wanted
Loaded the project and picture
I hope this helps if not please reply back

Also 2011 broke CapturePreviewImage but it is supposed to be fixed in the Update
I have MEP installed and they have not released the update's for the vertical autocad's so I do not know if it works yet .

Click the folder then select a folder than select a file

Here is the code

command

Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.ApplicationServices.Application
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Runtime

Public Class Class1
    ''This is to command to Show the Form
    <CommandMethod("lbForm", CommandFlags.Modal)>
    Public Sub lbForm()
        Dim frm As New Form1
        Application.ShowModalDialog(frm)
    End Sub
End Class

form

Imports System.IO
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.ApplicationServices.Application
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Runtime
Imports System.Drawing
Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If Fbd.ShowDialog = Windows.Forms.DialogResult.OK Then
            lstbxFiles.Items.Clear()
            For Each fName In Directory.GetFiles(Fbd.SelectedPath, "*.dwg")
                Me.lstbxFiles.Items.Add(fName)
            Next
        End If
    End Sub

    Private Sub lstbxFiles_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lstbxFiles.SelectedIndexChanged
        Dim db As Database = New Database(False, False)
        Dim fname As String = lstbxFiles.SelectedItem.ToString()
        db.ReadDwgFile(fname, FileOpenMode.OpenForReadAndReadShare, False, "")
        Dim tmbNail As Bitmap = db.ThumbnailBitmap
        picBox.Image = tmbNail
    End Sub
End Class