This is useful when you are creating drawings from a template that has inserted blocks or pre-drawn objects. It is also helps when creating many CNC drawings. Instead of creating a new drawing each time, just create one drawing, create objects, save as, delete all, create objects, save as, and repeat until all the CNC drawings are created. This is a much faster process.
There are two methods that can be used. The first will create a selection set and delete all the objects in that selection set. The second will create the selection set and delete each entity in the selection with a loop. The first method is much faster but will not always work and will sometimes result in an ‘invalid entity name’ error.
Note these modules are written and run from inside an excel file. They can also be written in an AutoCAD file vba module. Just replace acadDoc with ThisDrawing. Also there is no need to get acadApp object when running from inside AutoCAD drawing.
Sub delete_all()
Dim acadDoc As Object
Dim acadApp As Object
Dim objss As AcadSelectionSet
On Error Resume Next
Set acadApp = GetObject(, "AutoCAD.Application")
acadApp.Visible = True
If acadApp Is Nothing Then
Set acadApp = CreateObject("AutoCAD.Application")
acadApp.Visible = True
End If
If acadApp Is Nothing Then
MsgBox "Sorry, it was impossible to get AutoCAD!", vbCritical, "AutoCAD Error"
Exit Sub
End If
acadApp.WindowState = acMax
Set acadDoc = acadApp.ActiveDocument
acadDoc.ActiveSpace = acModelSpace
Set objss = acadDoc.SelectionSets.Add("ToErase")
objss.Select acSelectionSetAll 'select all entities (no filters)
objss.Erase 'erase the selection
objss.Delete 'delete the selection set object (not the entities)
acadDoc.Regen acAllViewports
On Error GoTo 0
End Sub
Sub delete_all_loop()
Dim acadDoc As Object
Dim acadApp As Object
Dim objdrawingobject As AcadEntity
Dim objss As AcadSelectionSet
On Error Resume Next
Set acadApp = GetObject(, "AutoCAD.Application")
acadApp.Visible = True
If acadApp Is Nothing Then
Set acadApp = CreateObject("AutoCAD.Application")
acadApp.Visible = True
End If
If acadApp Is Nothing Then
MsgBox "Sorry, it was impossible to get AutoCAD!", vbCritical, "AutoCAD Error"
Exit Sub
End If
acadApp.WindowState = acMax
Set acadDoc = acadApp.ActiveDocument
acadDoc.ActiveSpace = acModelSpace
Set objss = acadDoc.SelectionSets.Add("ToErase")
objss.Select acSelectionSetAll
For Each objdrawingobject In objss
objdrawingobject.Delete
Next
objss.Delete
acadDoc.Regen acAllViewports
On Error GoTo 0
End Sub
Coding with Visual Basic 