Add a New Member to a Collection Object
Collection Objects
Delete a Member of a Collection Object
To select a specific member of a Collection object, use the Item method. The Item method requires an identifier as either an index number specifying the location of the item within the collection or a string representing the name of the item.
The Item method is the default method for a collection. If you do not specify a method name when referring to a collection, Item is assumed. The following statements are equivalent:
ThisDrawing.Layers.Item("ABC")
ThisDrawing.Layers("ABC")
NoteDo
not use the entity edit methods (Copy, Array, Mirror, and so forth) on
any object while simultaneously iterating through a collection using
the For Each mechanism. Either finish your iteration before you
attempt to edit an object in the collection or create a temporary
array and set it equal to the collection. Then you can iterate through
the copied array and perform your edits.
Iteratethrough the Layers collection
The following example iterates through a collection and displays the names of all layers in the collection:
Sub Ch2_IterateLayer()
' Iterate through the collection
On Error Resume Next
Dim I As Integer
Dim msg As String
msg = ""
For I = 0 To ThisDrawing.Layers.count - 1
msg = msg + ThisDrawing.Layers.Item(I).Name + vbCrLf
Next
MsgBox msg
End Sub
The following example refers to layer named MyLayer, and issues a message if the layer does not exist:
Sub Ch2_FindLayer()
' Use the Item method to find a layer named MyLayer
On Error Resume Next
Dim ABCLayer As AcadLayer
Set ABCLayer = ThisDrawing.Layers("MyLayer")
If Err <> 0 Then
MsgBox "The layer 'MyLayer' does not exist."
End If
End Sub