VB Collection.Add - Default value for Before argument

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Hi,
I am getting "Invalid Procedure Call or Argument" debug error from below lines

VB

Public Function SomeMethod
   Dim pos As Integer
   If <<Some Condition>> Then
      pos = 1
   End If
   
   myCol.Add myOjb, myKey, Before:=pos
End Function

I want the object to be added to the last if condition not met. If condition is met then add at the specified index.

It was working fine just before I added Before argument. But not sure what is wrong with the last argument

Posted 7-Sep-15 5:11am

yash35

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Comments

Wombaticus 7-Sep-15 12:43pm

If thr condition is not met in your code above, then pos is left undefined

2 solutions

Solution 2

I'd recommend to read these:
Sub Procedures (Visual Basic)[^]
Collections in Visual Basic[^]

I would do that this way:

VB

Public Function SomeMethod(Optional ByVal pos As Integer = 1)
   myCol.Add myOjb, myKey, Before:=pos
End Function

Why?

MSDN wrote:
Before

Optional. An expression that specifies a relative position in the collection. The element to be added is placed in the collection before the element identified by the Before argument. If Before is a numeric expression, it must be a number from 1 through the value of the collection's Count Property (Collection Object). If Before is a String expression, it must correspond to the key string specified when the element being referred to was added to the collection. You cannot specify both Before and After.

Source: Add Method (Collection Object)[^]

Posted 7-Sep-15 8:52am

Maciej Los

Updated 7-Sep-15 8:55am

v2

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CPallini · Accepted Answer · 2015-09-07T06:42:00

Solution 1

If the condition is not met then pos is not initialized. You might write, for instance

VB

If <<Some Condition>> Then
   myCol.Add myOjb, myKey, Before:=1
Else
   myCol.Add myOjb, myKey
End If

Posted 7-Sep-15 6:42am

CPallini

Comments

Maciej Los 7-Sep-15 14:55pm

Good advice, +5!

yash35 8-Sep-15 2:59am

Can I modify this as below, since I have more conditions to check for and pos varies

If <<Some Condition>> Then
myCol.Add myOjb, myKey, Before:=pos
Else
myCol.Add myOjb, myKey
End If