The variables for raster images are stored in the Named Object Dictionary (NOD) in the database with the key name "ACAD_IMAGE_VARS". Using the .NET API, you can open this entry in the NOD as RasterVariables object.
Here is a VB.NET example that sets the IMAGEFRAME variable to zero (Image frames are not displayed and not plotted).
<CommandMethod("ImageFrameOff")> _
Public Sub CmdImageFrameOff()
Dim db As Database = Application.DocumentManager.
MdiActiveDocument.Database
Using trans As Transaction=db.TransactionManager.StartTransaction()
Try
Dim theNOD As DBDictionary = trans.GetObject(
db.NamedObjectsDictionaryId, OpenMode.ForRead)
Dim rasterVars As RasterVariables
'get variables dictionary
Dim kImageVars As String = "ACAD_IMAGE_VARS"
If theNOD.Contains(kImageVars) Then
Dim rastVarsId As ObjectId = theNOD.GetAt(kImageVars)
rasterVars = trans.GetObject(rastVarsId, OpenMode.ForWrite)
Else
' or create it
rasterVars = New RasterVariables()
theNOD.UpgradeOpen()
theNOD.SetAt(kImageVars, rasterVars)
trans.AddNewlyCreatedDBObject(rasterVars, True)
End If
rasterVars.ImageFrame = FrameSetting.ImageFrameOff
trans.Commit()
Catch
End Try
End Using
End Sub