Closing a MDI Child from the MDI parent throws an exception

[Guest]

Hello:

In the closing event of the MDI Parent, I have the following routine:

While Me.MdiChildren.Length > 0
liCounter = Me.MdiChildren.Length
Me.MdiChildren(liCounter - 1).Close()
End While

When I do have a MI Child, the .Close statement throws an exception, "Object
reference not set to an instance of an object".

What am I doing wrong?

Venki

 

[Eric Moreau]

try this:

for each x as form in me.mdichildren
x.close
next

--


HTH

Éric Moreau, MCSD, Visual Developer - Visual Basic MVP
(http://aspnet2.com/mvp.ashx?EricMoreau)
Conseiller Principal / Senior Consultant
Concept S2i inc. (www.s2i.com)

 

[C-Services Holland b.v.]

Hello:

In the closing event of the MDI Parent, I have the following routine:

While Me.MdiChildren.Length > 0
liCounter = Me.MdiChildren.Length
Me.MdiChildren(liCounter - 1).Close()
End While

When I do have a MI Child, the .Close statement throws an exception, "Object
reference not set to an instance of an object".

What am I doing wrong?

Venki

Try changing this line:
Me.MdiChildren(liCounter - 1).Close()
to
Me.MdiChildren(0).Close()

 

[Guest]

Eric:

It raises the same exception, "Run-time exception thrown :
System.NullReferenceException - Object reference not set to an instance of an
object."

I am stumped!

Venki

 

[Guest]

Eric:

I see the following sequence of events when I close the MDIParent Window:

1. It closes the MDI Child Frm, triggers the closing event of the MDIChild
form.
2. Then it triggers the MDI Parent's closing event. But Me.MIDChildren.Count
is still 1, even though the MDI Child form has already been closed.
3. This raised the exception.

Any more ideas?