arc properties

Why do some AcadArc entities have a startangle and endangle but not
startpoint and endpoint? Startangle and Endangle are recognized as valid
properties of the problem arc. Try to check Startpoint or Endpoint and I get
"run-time error '451' Property let procedure not defined and property get
procedure did not return an object". If I check with lbound(arc.startpoint)
it returns 0 and ubound(arc.startpoint) returns 2. Yet every attempt to
access arc.startpoint(0) gives me the error.

thanks
LJB

 

What would I ever do without the help I receive from this newsgroup?!?!

 

In my case I have to pass the entity to another subroutine. Passing it as a variant or object sometimes I can't get to the properties. However passing it as a specific type fixes it every time.



"joesu" <> wrote in message news:...

There is no need to cast the objects to AcadArc. Here is an example.

Joe
--

Public Sub ArcDetail() Dim oSS As AcadSelectionSet Dim oEntity As AcadEntity Dim iFilterCode(0) As Integer Dim vFilterValue(0) As Variant

On Error Resume Next   Application.ActiveDocument.SelectionSets("Arcs").Delete   On Error GoTo 0

Set oSS = Application.ActiveDocument.SelectionSets.Add("Arcs")   iFilterCode(0) = 0: vFilterValue(0) = "Arc"   oSS.SelectOnScreen iFilterCode, vFilterValue   If oSS.Count Then     For Each oEntity In oSS       Dim oArc As AcadArc       Set oArc = oEntity       With oArc         MsgBox "StartPoint: " & .StartPoint(0) & ", " & .StartPoint(1) & ", " & .StartPoint(2) & vbCrLf & _                "EndPoint : " & .EndPoint(0) & ", " & .EndPoint(1) & ", " & .EndPoint(2)       End With     Next oEntity   End If End Sub

 

True, VB doesn't have anything to cast a variable to another type. In my
case it was really assignment to another type as in:

Dim v as Variant
Dim arc as AcadArc

Set arc = v

y = v.xx 'may not always work
y = arc.xx 'reveals the properties OK

 

Hi James,

Assume you have an unfiltered selection set [oSS] and you want to get at the start and end points of a line object

For Each oEntity In oSS   If TypeOf oEntity Is AcadLine Then     Set oLine = oEntity 'cast the generic entity to a line     MsgBox oLine.StartPoint(0) ...   End If Next oEntity

In this example, you cast the generic object of AcadEntity datatype to be the more specific AcadLine datatype. You do this because the AcadEntity datatype does not support a StartPoint or EndPoint property. Does this help clear up the confusion a bit?

Joe
--

 

No confusion here, Joe... I was just mis-reading your post and inferring
things. You said there is no need to cast, and then your example *appeared*
to cast... or at least the VBA equivalent of casting. So I thought I saw a
contradiction. But I guess you were saying, roughly... "You don't need to
cast -- instead, you should hold it in an AcadArc variable"

James

 

Actually my ArcDetails routine is incorrect. It has a cast which is not necessary since I'm creating a filtered selection of just arcs. Here is the corrected version.

Joe
--

Public Sub ArcDetail() Dim oSS As AcadSelectionSet Dim oArc As AcadArc Dim iFilterCode(0) As Integer Dim vFilterValue(0) As Variant

On Error Resume Next   Application.ActiveDocument.SelectionSets("Arcs").Delete   On Error GoTo 0

Set oSS = Application.ActiveDocument.SelectionSets.Add("Arcs")   iFilterCode(0) = 0: vFilterValue(0) = "Arc"   oSS.SelectOnScreen iFilterCode, vFilterValue   If oSS.Count Then     For Each oArc In oSS       With oArc         MsgBox "StartPoint: " & .StartPoint(0) & ", " & .StartPoint(1) & ", " & .StartPoint(2) & vbCrLf & _                "EndPoint : " & .EndPoint(0) & ", " & .EndPoint(1) & ", " & .EndPoint(2)       End With     Next oArc   End If End Sub