Solved

object not set to instance of object when declaring a partial class

Posted on 2011-03-09
6
348 Views
Last Modified: 2012-05-11
Hello experts,
I normally know how to fix this, and its usually because i forgot a new keyword somewhere.  That is not the case.  I am using a partial class that generates a serialized xml.  I create a new instance of the class but it is still telling me object not set to instance of an object.   I used the xsd tool to create the class from a provided schema.  The generated class is below, i took out a lot of unecessary variables.  I have never worked with partial classes so i am wondering if that is the cause.

In my code i call the below class like so:
Function create_receipt_xml(byval bod_id as string) As Boolean
        Dim as2 As New ShowReceiptInfo
        Dim serializer = New XmlSerializer(GetType(ShowReceiptInfo))

        Try
            as2.ApplicationArea.BODId = bod_id  'I get the object not set to instance of object here
            header_info ="test"
           Dim string_writer As New StringWriter()
            serializer.Serialize(string_writer, as2)
            Dim LogDir As String = System.Configuration.ConfigurationSettings.AppSettings("LogDirectory")
            Log_Files(LogDir, string_writer.ToString(), headerid)

            'Send_Transaction(string_writer.ToString(), HeaderId, strURL)
            string_writer.Close()
            string_writer.Dispose()
            as2 = Nothing
        Catch ex As Exception
            MessageBox.Show("Failed to create int100 xml! " & ex.Message)
        End Try
    End Function
'------------------------------------------------------------------------------
' <auto-generated>
'     This code was generated by a tool.
'     Runtime Version:2.0.50727.3615
'
'     Changes to this file may cause incorrect behavior and will be lost if
'     the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------

Option Strict Off
Option Explicit On

Imports System.Xml.Serialization

'
'This source code was auto-generated by xsd, Version=2.0.50727.42.
'

'''<remarks/>
<System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.42"), _
 System.SerializableAttribute(), _
 System.Diagnostics.DebuggerStepThroughAttribute(), _
 System.ComponentModel.DesignerCategoryAttribute("code"), _
 System.Xml.Serialization.XmlTypeAttribute(AnonymousType:=True, [Namespace]:="http://mycompany.com/manufac"), _
 System.Xml.Serialization.XmlRootAttribute([Namespace]:="http://mycompany.com/ manufac ", IsNullable:=False)> _
Partial Public Class ShowReceiptInfo

    Private applicationAreaField As ShowReceiptInfoApplicationArea
    '''<remarks/>
    <System.Xml.Serialization.XmlElementAttribute(Form:=System.Xml.Schema.XmlSchemaForm.Unqualified)> _
    Public Property ApplicationArea() As ShowReceiptInfoApplicationArea
        Get
            Return Me.applicationAreaField
        End Get
        Set(ByVal value As ShowReceiptInfoApplicationArea)
            Me.applicationAreaField = value
        End Set
    End Property

    End Property
End Class

'''<remarks/>
<System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.42"),  _
 System.SerializableAttribute(),  _
 System.Diagnostics.DebuggerStepThroughAttribute(),  _
 System.ComponentModel.DesignerCategoryAttribute("code"),  _
 System.Xml.Serialization.XmlTypeAttribute(AnonymousType:=true, [Namespace]:="http://mycompany.com/manufac ")>  _
Partial Public Class ShowReceiptInfoApplicationArea
    
    Private bODIdField As String
    
<System.Xml.Serialization.XmlElementAttribute(Form:=System.Xml.Schema.XmlSchemaForm.Unqualified)>  _
    Public Property BODId() As String
        Get
            Return Me.bODIdField
        End Get
        Set
            Me.bODIdField = value
        End Set
    End Property
    
End Class

Open in new window

0
Comment
Question by:tentavarious
  • 4
  • 2
6 Comments
 
LVL 4

Expert Comment

by:parnasso
Comment Utility
I think the compiler is telling you that the variable applicationAreaField has not been initialized. When declaring a class partial, the default constructor for your ShowReceiptInfo class is not doing something like : Dim applicationAreaField As New ShowReceiptInfoApplicationArea.

Declare another Partial Public Class ShowReceiptInfo with a default constructor that initializes the field applicationAreaField.

I hope my explanation was clear

0
 

Author Comment

by:tentavarious
Comment Utility
Here is the xml schema i used to create class above

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified"
           targetNamespace="http://mycompany.com/manufac "
           xmlns:pre="http://mycompany.com/manufac">
  <xs:element name="ShowReceiptInfo">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="ApplicationArea" form="unqualified">
                  <xs:element name="BODId" form="unqualified" type="xs:string"/>
              </xs:sequence>
          </xs:complexType>
        </xs:element>
       <xs:attribute name="environment" use="required"/>
      <xs:attribute name="lang" use="required"/>
      <xs:attribute name="revision" use="required"/>
    </xs:complexType>
  </xs:element>
</xs:schema>
0
 

Author Comment

by:tentavarious
Comment Utility
Could you provide an example, the code compiles fine, i get the error when i try and run it
0
How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

 
LVL 4

Accepted Solution

by:
parnasso earned 500 total points
Comment Utility
I didn't explained myself clearly. In addition to the code which is generated automatically, you can declare in your manually written code another part of the partial class:

Partial Public Class ShowReceiptInfo

    Private applicationAreaField As ShowReceiptInfoApplicationArea

    Private Sub Constructor()
        applicationAreaField =  New ShowReceiptInfoApplicationArea; // or default value you want
    End Sub

Open in new window


Then when you do in your code:

 as2.ApplicationArea.BODId = bod_id

It will work because the ApplicationArea now is not null.

By the way I'm sorry about the syntax errors in my VB.

0
 

Author Comment

by:tentavarious
Comment Utility
Still no go
I tried adding the constructor and  doing this

Private applicationAreaField As New ShowReceiptInfoApplicationArea
0
 

Author Comment

by:tentavarious
Comment Utility
Alright it worked thanks a lot, maybe you could take a look at another xml issue i am having.  It deals with the same project,  for some reason when i create the xml any tag i have containing a ":" gets replaced

take a look at this thread

http://www.experts-exchange.com/Programming/Languages/.NET/Visual_Basic.NET/Q_26870958.html
0

Featured Post

Highfive + Dolby Voice = No More Audio Complaints!

Poor audio quality is one of the top reasons people don’t use video conferencing. Get the crispest, clearest audio powered by Dolby Voice in every meeting. Highfive and Dolby Voice deliver the best video conferencing and audio experience for every meeting and every room.

Join & Write a Comment

More often than not, we developers are confronted with a need: a need to make some kind of magic happen via code. Whether it is for a client, for the boss, or for our own personal projects, the need must be satisfied. Most of the time, the Framework…
Today I had a very interesting conundrum that had to get solved quickly. Needless to say, it wasn't resolved quickly because when we needed it we were very rushed, but as soon as the conference call was over and I took a step back I saw the correct …
Internet Business Fax to Email Made Easy - With eFax Corporate (http://www.enterprise.efax.com), you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, fr…
This video discusses moving either the default database or any database to a new volume.

771 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now