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System.NullReferenceException

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This is a migrated thread and some comments may be shown as answers.
Karl
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Karl asked on 15 May 2010, 03:09 PM
I have a form in a WindowsApplication with just a RadTreeNode on it.


Imports System  
Imports Telerik.WinControls.UI  
 
Public Class Form1  
    Inherits Form  
    Private Sub Form1_Load(ByVal sender As System.ObjectByVal e As System.EventArgs) Handles MyBase.Load  
        InitializeComponent()  
 
        Dim node As RadTreeNode = RadTreeView1.Nodes("Email Contacts").Nodes.Add("Bob Tony")  
        node.Selected = True 
        RadTreeView1.Nodes("Email Contacts").Nodes.Add("Sue Winchell")  
        RadTreeView1.Nodes("Email Contacts").Nodes.Add("Lui Sang")  
        RadTreeView1.Nodes("Lists").Nodes.Add("Priorities")  
        RadTreeView1.Nodes("Lists").Nodes.Add("Opportunities")  
        RadTreeView1.Nodes("Lists").Nodes.Add("Issues")  
    End Sub 
End Class 

This is from your example.
On reaching this line:
        Dim node As RadTreeNode = RadTreeView1.Nodes("Email Contacts").Nodes.Add("Bob Tony")  
I keep getting the error:
System.NullReferenceException was unhandled
  Message="Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt."

What's happening and how do I correct it?

Thanks in advance
Karl
 

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Karl
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answered on 16 May 2010, 10:59 AM
Found it.
RadTreeView1.Nodes("Email Contacts"). doesn't exist - fist has to be added.
and
InitializeComponent()
was disturbing
thanks anyway
0
Victor
Telerik team
answered on 19 May 2010, 03:30 PM
Hello Karl,

It is great that you managed to find a solution.
Write again if you have other questions.

Sincerely yours,
Victor
the Telerik team

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Karl
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Victor
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