Ad:

VB.NET Discussion Thread
Unsolved
Views: 1075

Jul 4th, 2009

Writing to an XML without overwriting data

Expand Post »

Ive managed so far with this code that amends data to an xml form, but I need to figure out how to remove the bit of code that amends data rather than overwriting it. Ive messed around with the code to see if I could manipulate it myself to get be able to overwrite data, but I havent been able to, so I ask for help.

vb.net Syntax (Toggle Plain Text)
ElseIf ComboBox1.Text = "Turbine Data" Then
            'start of first combo box code
            Dim filepath As String = My.Application.Info.DirectoryPath & turbdatxml
 
            If Dir(filepath) <> "" Then
 
                If (TextBox1.Text.Equals("") Or TextBox2.Text.Equals("") Or TextBox3.Text.Equals("") Or TextBox4.Text.Equals("")) Then
 
                    MsgBox(val_txt, , inval_title)
 
                Else
                    Dim ExistingData As New MyDatum
 
                    Dim Serializer As New System.Xml.Serialization.XmlSerializer(GetType(MyDatum))
 
                    If (File.Exists(filepath)) Then '& Not EOF(1)
 
                        'Need to find out how to check End of File, and skip this bit of code if file is empty
 
                        Dim OpenStream As System.IO.FileStream = System.IO.File.Open(filepath, IO.FileMode.Open)
 
                        'Protects existing data, to make a list, rather than overwriting data.
                        ExistingData = Serializer.Deserialize(OpenStream)
 
                        OpenStream.Close()
                    Else
 
                        MsgBox(cre05, , err05)
 
                    End If
 
                    Dim NewData As New MyData
 
                    TextBox1.Focus()
                    NewData.DateStamp = CDate(Date.Today()) 'DateValue(Now)
                    NewData.TimeStamp = CDate(TimeString())
                    'find out how to display the date and time seperate, not as a stamp
                    NewData.Gap = gaptext.Text
                    NewData.Diameter = diatext.Text
                    NewData.R2 = TextBox1.Text
                    NewData.VentDiamater = TextBox2.Text
                    NewData.R1 = TextBox3.Text
                    NewData.Height = TextBox4.Text
 
                    ExistingData.Add(NewData)
 
                    Dim SaveStream As System.IO.FileStream = System.IO.File.Open(filepath, IO.FileMode.Open)
                    ' IO.FileMode.Create or .Open
 
                    Serializer.Serialize(SaveStream, ExistingData)
 
                    SaveStream.Close()
 
                    MsgBox("Data Saved to " & filepath, , _save)
 
                End If
 
            Else
 
                MsgBox(cre05, , err05)
 
                Dim ExistingData As New MyDatum
                Dim Serializer As New System.Xml.Serialization.XmlSerializer(GetType(MyDatum))
                Dim NewData As New MyData
                Dim SaveStream As System.IO.FileStream = System.IO.File.Open(filepath, IO.FileMode.Create)
 
                TextBox1.Focus()
                NewData.DateStamp = CDate(Date.Today()) 'DateValue(Now)
                NewData.TimeStamp = CDate(TimeString())
                NewData.Gap = gaptext.Text
                NewData.Diameter = diatext.Text
                NewData.R2 = TextBox1.Text
                NewData.VentDiamater = TextBox2.Text
                NewData.R1 = TextBox3.Text
                NewData.Height = TextBox4.Text
 
                Serializer.Serialize(SaveStream, ExistingData)
                SaveStream.Close()
            End If
            'End of first combo box code
ElseIf ComboBox1.Text = "Turbine Data" Then
            'start of first combo box code
            Dim filepath As String = My.Application.Info.DirectoryPath & turbdatxml

            If Dir(filepath) <> "" Then

                If (TextBox1.Text.Equals("") Or TextBox2.Text.Equals("") Or TextBox3.Text.Equals("") Or TextBox4.Text.Equals("")) Then

                    MsgBox(val_txt, , inval_title)

                Else
                    Dim ExistingData As New MyDatum

                    Dim Serializer As New System.Xml.Serialization.XmlSerializer(GetType(MyDatum))

                    If (File.Exists(filepath)) Then '& Not EOF(1)

                        'Need to find out how to check End of File, and skip this bit of code if file is empty

                        Dim OpenStream As System.IO.FileStream = System.IO.File.Open(filepath, IO.FileMode.Open)

                        'Protects existing data, to make a list, rather than overwriting data.
                        ExistingData = Serializer.Deserialize(OpenStream)

                        OpenStream.Close()
                    Else

                        MsgBox(cre05, , err05)

                    End If

                    Dim NewData As New MyData

                    TextBox1.Focus()
                    NewData.DateStamp = CDate(Date.Today()) 'DateValue(Now)
                    NewData.TimeStamp = CDate(TimeString())
                    'find out how to display the date and time seperate, not as a stamp
                    NewData.Gap = gaptext.Text
                    NewData.Diameter = diatext.Text
                    NewData.R2 = TextBox1.Text
                    NewData.VentDiamater = TextBox2.Text
                    NewData.R1 = TextBox3.Text
                    NewData.Height = TextBox4.Text

                    ExistingData.Add(NewData)

                    Dim SaveStream As System.IO.FileStream = System.IO.File.Open(filepath, IO.FileMode.Open)
                    ' IO.FileMode.Create or .Open

                    Serializer.Serialize(SaveStream, ExistingData)

                    SaveStream.Close()

                    MsgBox("Data Saved to " & filepath, , _save)

                End If

            Else

                MsgBox(cre05, , err05)

                Dim ExistingData As New MyDatum
                Dim Serializer As New System.Xml.Serialization.XmlSerializer(GetType(MyDatum))
                Dim NewData As New MyData
                Dim SaveStream As System.IO.FileStream = System.IO.File.Open(filepath, IO.FileMode.Create)

                TextBox1.Focus()
                NewData.DateStamp = CDate(Date.Today()) 'DateValue(Now)
                NewData.TimeStamp = CDate(TimeString())
                NewData.Gap = gaptext.Text
                NewData.Diameter = diatext.Text
                NewData.R2 = TextBox1.Text
                NewData.VentDiamater = TextBox2.Text
                NewData.R1 = TextBox3.Text
                NewData.Height = TextBox4.Text

                Serializer.Serialize(SaveStream, ExistingData)
                SaveStream.Close()
            End If
            'End of first combo box code

I need to keep with this original code as far as the serializing of the data is concerned, I just need to remove the 'ExistingData' component from the code, and still be able to write data to the xml.

Similar Threads

Writing mp3 files to data files in Mac OS X
data to be displayed in xml in PHP
Reading and writing to XML file with ActionScript in IT Professionals' Lounge
Reading and writing to XML file with ActionScript in Graphics and Multimedia
Help with Reading/Editing/Writing XML data in .NET in XML, XSLT and XPATH

Tamir09

Reputation Points: 10

Solved Threads: 0

Light Poster

Offline

27 posts
since Feb 2009

Permalink

Jul 5th, 2009

Re: Writing to an XML without overwriting data

Tamir09,

Quote ...

I need to keep with this original code as far as the serializing of the data is concerned, I just need to remove the 'ExistingData' component from the code, and still be able to write data to the xml.

Do you want to modify the XML document or your source code?

adatapost

Moderator

Reputation Points: 2136

Solved Threads: 1228

Posting Genius

Offline

6,527 posts
since Oct 2008

Permalink

Jul 5th, 2009

Re: Writing to an XML without overwriting data

I would prefer to modify my source code.

Tamir09

Reputation Points: 10

Solved Threads: 0

Light Poster

Offline

27 posts
since Feb 2009

Permalink

Jul 7th, 2009

Re: Writing to an XML without overwriting data

Any help would be appreciated...

Tamir09

Reputation Points: 10

Solved Threads: 0

Light Poster

Offline

27 posts
since Feb 2009

Permalink

Jul 7th, 2009

Re: Writing to an XML without overwriting data

Use DOM.

adatapost

Moderator

Reputation Points: 2136

Solved Threads: 1228

Posting Genius

Offline

6,527 posts
since Oct 2008

Permalink

Jul 7th, 2009

Re: Writing to an XML without overwriting data

Click to Expand / Collapse Quote originally posted by adatapost ...

Use DOM.

What is DOM? And how will I be able to apply that to my code?

Last edited by Tamir09; Jul 7th, 2009 at 11:49 pm.

Tamir09

Reputation Points: 10

Solved Threads: 0

Light Poster

Offline

27 posts
since Feb 2009

Permalink

Jul 8th, 2009

Re: Writing to an XML without overwriting data

Document Object Model - a standard to work with XML document. See the System.XML namespace.

VB.NET Syntax (Toggle Plain Text)
Dim doc as New  System.Xml.XmlDocument()
doc.Load("file.xml") 'Load an XML document
...
...
doc.Save("file.xml") 'Save the document
Dim doc as New  System.Xml.XmlDocument()
doc.Load("file.xml") 'Load an XML document
...
...
doc.Save("file.xml") 'Save the document

adatapost

Moderator

Reputation Points: 2136

Solved Threads: 1228

Posting Genius

Offline

6,527 posts
since Oct 2008

Permalink

Jul 8th, 2009

Re: Writing to an XML without overwriting data

Thanks for the suggestions, but my question is how I can change my current code to allow for overwriting my xml data?

Tamir09

Reputation Points: 10

Solved Threads: 0

Light Poster

Offline

27 posts
since Feb 2009

This thread is more than three months old

No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.

Previous Thread in VB.NET Forum Timeline: how to Access Module variable in ToolStripMenuItem_Click Event

Next Thread in VB.NET Forum Timeline: How do i use the keyboard in my code?

DaniWeb Message

Cancel Changes

User Name
Password