Writing to an XML without overwriting data
 

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.

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.

Re: Writing to an XML without overwriting data
 

Tamir09,
Do you want to modify the XML document or your source code?

Re: Writing to an XML without overwriting data
 

I would prefer to modify my source code.

Re: Writing to an XML without overwriting data
 

Any help would be appreciated...

Re: Writing to an XML without overwriting data
 

Use DOM.

Re: Writing to an XML without overwriting data
 

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

Re: Writing to an XML without overwriting data
 

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

Dim doc as New  System.Xml.XmlDocument()

doc.Load("file.xml") 'Load an XML document

...

...

doc.Save("file.xml") 'Save the document

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?