I have error in this code:

Dim Doc As XmlDocument = New XmlDocument

Dim Attrb As XmlAttribute

Try

Doc.Load(Application.StartupPath & "\EmployeeDB.xml")

Catch ex As Exception

Dim Dec As XmlDeclaration = Doc.CreateXmlDeclaration("1.0", "utf-8", Nothing) : Doc.AppendChild(Dec)

End Try

Dim Root As XmlElement = Doc.CreateElement("Section")

Attrb = Doc.CreateAttribute("Index") : Attrb.InnerText = ComboBox1.SelectedIndex

Root.Attributes.Append(Attrb) : Doc.AppendChild(Root)

Dim Child As XmlNode = Doc.CreateElement("Employee")

Attrb = Doc.CreateAttribute("Name") : Attrb.InnerText = TextBox1.Text

Child.Attributes.Append(Attrb) : Root.AppendChild(Child)

Dim SubChild As XmlNode

SubChild = Doc.CreateElement("ID") : SubChild.InnerText = TextBox2.Text

Child.AppendChild(SubChild)

SubChild = Doc.CreateElement("Number") : SubChild.InnerText = TextBox3.Text

Child.AppendChild(SubChild)

SubChild = Doc.CreateElement("Jop") : SubChild.InnerText = TextBox4.Text

Child.AppendChild(SubChild)

Doc.Save(Application.StartupPath & "\EmployeeDB.xml")

In first time it's work fine but when I try to add another data I get this error "This document already has a 'DocumentElement' node." in Doc.AppendChild(Root)

The error is thrown because you are trying to add a start element (Document element) to a xmlDoc which already has a Document Element.

Try this :

Doc.DocumentElement.AppendChild(Root)

Hope this helps...

Regards...

Girija Shankar

Try this :

In place of :Root.AppendChild(Child)

in this statement : Child.Attributes.Append(Attrb) : Root.AppendChild(Child)

use:

(I am writing in C#)

if (Root.ChildNodes > 0)

{

Root.FirstChild.AppendChild(Child)

}

else

Root.ChildNodes[0] = Child;

Hope this helps ..

Let me know if this works

Regards..

Girija Shankar

Sorry Wrong Code :

if (Root.ChildNodes.Count > 0)

{

Root.FirstChild.AppendChild(Child)

}

else

Root.ChildNodes[0] = Child;

Try this. Let me know if this works...

Regards..

Girija Shankar

Try this:

If Root.ChildNodes.Count > 0 Then
Root.FirstChild.AppendChild(Child)
Else
Root.ChildNodes.Item(0).AppendChild(Child)
End If

Regards..

Girija Shankar

Try this code .. This will work .. The one marked in Red is to be removed and marked in yellow to be added:

Dim Doc As XmlDocument = New XmlDocument
Dim Root As XmlElement = Doc.CreateElement("Section") : Root.SetAttribute("index", ComboBox1.SelectedIndex)
Dim Child As XmlElement = Doc.CreateElement("Employee") : Child.SetAttribute("Name", TextBox1.Text)
Dim SubChild1 As XmlElement = Doc.CreateElement("ID")
Dim SubChild2 As XmlElement = Doc.CreateElement("Number")
Dim SubChild3 As XmlElement = Doc.CreateElement("Jop")

Try
Doc.Load(Application.StartupPath & "\EmployeeDB.xml")
Catch ex As Exception
Dim Dec As XmlDeclaration = Doc.CreateXmlDeclaration("1.0", "utf-8", Nothing) : Doc.AppendChild(Dec)
End Try

Try
Doc.AppendChild(Root)
Catch ex As Exception
Doc.DocumentElement.AppendChild(Root)
End Try

If Root.ChildNodes.Count > 0 Then
Root.FirstChild.AppendChild(Child)
Else
Root.ChildNodes.Item(0).AppendChild(Child)
End If

Child.AppendChild(SubChild1) : SubChild1.InnerText = TextBox2.Text
Child.AppendChild(SubChild2) : SubChild2.InnerText = TextBox3.Text
Child.AppendChild(SubChild3) : SubChild3.InnerText = TextBox4.Text

Doc.DocumentElement.LastChild.AppendChild(Child)

Doc.Save(Application.StartupPath & "\EmployeeDB.xml")

I have highlighted in red in the quote the actual source of the issue. That line is creating the "Section" element, and adding it as the document element. Then, on the yellow line, you are trying to add the same element again as the root (also known as Document Element), so you get the error: "This document already has a 'DocumentElement' node. This happens because indeed, there is already a document element node in the document.

In theory, since the element is already added, you shouldn't add it again, so the yellow statement should simply be removed from the code.
If that doesn't work, try replacing the line with the red highlight with

Dim Root As New XmlElement("Section")
this will create the "Section" element, independently of the document, and assign the XmlElement object to the Root variable, so you can work with it. Then your code makes whatever it needs with it (like adding attributes, as you're doing), and only when you finally reach the Doc.AppendChild() call the element is added.

Hope this helps.

The reason why you are getting the above error is because you cannot have more than one Document Element.

Let me explain :

You can have a XML like this :

<?xml version="1.0" encoding="utf-8"?>

<RootElement>
<Section Index="2">
<Employee Name="Micheal">
<ID>1</ID>
<Number>1</Number>
<Jop>Nothing</Jop>
</Employee>
</Section>

<Section Index="3">
<Employee Name="chshcis">
<ID>1</ID>
<Number>1</Number>
<Jop>Nothing</Jop>
</Employee>
</Section>
</RootElement>

Mark the "Root Element" above.

You cannot have an XML document like this :

<?xml version="1.0" encoding="utf-8"?>
<Section Index="2">
<Employee Name="Micheal">
<ID>1</ID>
<Number>1</Number>
<Jop>Nothing</Jop>
</Employee>
</Section>

<Section Index="3">
<Employee Name="chshcis">
<ID>1</ID>
<Number>1</Number>
<Jop>Nothing</Jop>
</Employee>
</Section>

because in above xml you have two root elements (Section).

So basically you will have to check if the Document is emoty create a root element first, then start adding the Section elements.

For adding the Child node inside the section element, the last code should work. I suppose you are working with an emprt xmlDoc where i am working with a doc which has some root element .

Let me know if this doesnot work... Send me the XML file details that you are appending these elements to. That should help me.

I hope this helps you...

Regards...

Girija Shankar

Please make sure you mark the answer whichever is correct so that others know that this is resolved

Thanks ..

Regards...

Girija Shankar

You can store more than 1000 data. The speed will be quick.

Hope this helps..

Regards...

Girija Shankar