reading dwg file external to autocad

[agsingh]

Is there any way i can programmatically read autocad file .dwg and extract information file attributes, blocks, x-ref etc without opening autocad application.

 

[IFRs]

You'd have to know the dwg file structure. I don't think AutoCAD has put that in the public domain.

DXF is easy.

 

[agsingh]

how to change dwg files to dxf in batch.

 

[borgunit]

You need to make a reference to the ObjectDBX library in your project. You can open and browse though a closed drawing with it. We use Excel to check Titleblock attributes in drawings with this. Here is a snippet of code to look at a drawings blocks. It is based on the form I am using, but just look at how it queries the drawing... It uses a open method and then most other AutoCAD properties and methods are available to you. You cannot change and save to a closed drawing though. I hope this helps.
-------------------------------------

Private Sub CmdQueryDwg_Click()
Dim xDoc As Object 'AxDbDocument
Dim dwgFile As String
'''''''''''''''''''''''''''''''''''''''
dwgFile = txtOpenPath.Text

If dwgFile <> "" Then
Set xDoc = AcadApplication.GetInterfaceObject("ObjectDBX.AxDbDocument")
xDoc.Open dwgFile

ListBox1.Clear
If OptLayers.Value = True Then
Dim Layer As AcadLayer

For Each Layer In xDoc.Layers
ListBox1.AddItem (Layer.Name)
Next Layer
Else
Dim Block As AcadBlock
For Each Block In xDoc.Blocks
If ChkFilterBlks.Value = False Then
ListBox1.AddItem (Block.Name)
Else
If Left$(Block.Name, 1) <> "*" And _
Left$(Block.Name, 2) <> "A$" Then
ListBox1.AddItem (Block.Name)
End If
End If
Next Block
End If

End If
End Sub

"Everybody is ignorant, only on different subjects." — Will Rogers

 

[borgunit]

This link also gives a good example of pulling info from a closed drawing file..

http://www.cadmin.com/VBA_for_ADT/ObjectDBX.htm

"Everybody is ignorant, only on different subjects." — Will Rogers