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forms

If I click Button1, form2 show, then I click Button2 I get.

"An unhandled exception of type 'System.NullReferenceException' occurred in
WindowsApplication13.exe
Additional information: Object reference not set to an instance of an
object."

Why does ff = Nothing

Code on Form 1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button1.Click

Dim myfrom As New Form2

myfrom.Show()

End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button2.Click

Dim ff As Form2

Select Case ff.Visible

Case True

ff.Label1.Text = "This is form 2"

End Select

End Sub
Nov 20 '05 #1
3 990
You did not instantiate form in Button2_Click. Check how you do declare form
there.

HTH
Alex

"Simon Morris" <nz*********@hotmail.com> wrote in message
news:uK**************@TK2MSFTNGP12.phx.gbl...
If I click Button1, form2 show, then I click Button2 I get.

"An unhandled exception of type 'System.NullReferenceException' occurred in WindowsApplication13.exe
Additional information: Object reference not set to an instance of an
object."

Why does ff = Nothing

Code on Form 1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button1.Click

Dim myfrom As New Form2

myfrom.Show()

End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button2.Click

Dim ff As Form2

Select Case ff.Visible

Case True

ff.Label1.Text = "This is form 2"

End Select

End Sub

Nov 20 '05 #2
* "Simon Morris" <nz*********@hotmail.com> scripsit:
If I click Button1, form2 show, then I click Button2 I get.

"An unhandled exception of type 'System.NullReferenceException' occurred in
WindowsApplication13.exe

Additional information: Object reference not set to an instance of an
object."

Why does ff = Nothing

Code on Form 1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button1.Click
Dim myfrom As New Form2
myfrom.Show()
End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button2.Click
Dim ff As Form2
Select Case ff.Visible
Case True
ff.Label1.Text = "This is form 2"
End Select
End Sub


You need a _reference_ to your _instance_ of the form, for example:

<http://www.google.com/groups?ie=UTF-8&frame=right&th=9581aa445dfc4199&seekm=uDwbjx0EDH A.1660%40TK2MSFTNGP10.phx.gbl#link2>

Please do not post questions like this to the general VS.NET group, this
group is about VS.NET IDE questions.

--
Herfried K. Wagner
MVP · VB Classic, VB.NET
<http://www.mvps.org/dotnet>

<http://www.plig.net/nnq/nquote.html>
Nov 20 '05 #3
Do you mean

Dim ff As New Form2

instead of

Dim ff As Form2

Nov 20 '05 #4

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