Check if titleblockdefiition exists

[frederic.vandenplas]

How to avoid an error is thrown if titleblockdefinition does not exist?

I could use try catch, on error resume next and so on,  but this is a bad practice if you know that something can go wrong (in this case, the titleblockdef is not present) 

Sub testtitleblock()
 Dim oDrawDoc As DrawingDocument
 Set oDrawDoc = ThisApplication.ActiveDocument
 
 If oDrawDoc.TitleBlockDefinitions.Item("Notexistingtitleblockdef") Is Nothing Then
 MsgBox "not found"
 End If
 
End Sub

[MechMachineMan · Accepted solution]

I dont think it's necessarily a bad practice as long as you understand what you are doing.

I've run into cases where finding if a value exists in a large collection or enum is done most simply and quickly by trying to call that specific item, but catching the error for it it fails and returning the results.

The other option is looping through the collection:

Function TBExists(oTBName) As Boolean
     Exists = False
     For Each oTB in oDrawDoc.TitleBlockDefinitions
               If oTB.Name = oTBName Then
                        Exists = True
               End if
      Next
      Return Exists
End Function

[frederic.vandenplas]

@MechMachineMan

Thank you for this alternative, i ended up with this code (for those who are interested)

Dim boolBorderFound As Boolean = False
For Each oBorder In oDrawDoc.BorderDefinitions
   If oBorder.Name = oNewBorder Then
      boolBorderFound = True
   End If
Next oBorder
If boolBorderFound = False Then
   oNewborderDefinition = oSourceDrawDoc.BorderDefinitions.Item(oNewBorder).CopyTo(oDrawDoc, True)
End If